Chapter XIX: Part 19

_Centrosome._[25]--This minute body was first detected at the spindle poles by Flemming in 1875, and independently by P. J. van Beneden in 1876. The important part played by the centrosome in fertilization,[26] first described by van Beneden and Theodor Boveri in their papers of 1887-1888, together with the behaviour of this structure in mitosis, led these authors to regard the centrosome not only as the dynamic centre of the cell but as a permanent cell-organ, which, like the nucleus, passed by division from one cell-generation to the next. This conclusion appeared to receive considerable support from the recognition of the centrosome in various kinds of resting cells,[27] and especially from the relation this structure frequently shows to the locomotor apparatus of the cell (e.g. its position in the centre of the radiating fibrillae in the contractile lymph and pigment cells, and its relation to the vibratile flagellum in spermatozoa and some protozoa, e.g. Trypanosoma).[28] In almost all cases the centrosome of the resting cell, when this can be detected, lies in the cytoplasm, and is often already divided in preparation for the next mitotic division (e.g. spermatogenic cells of the salamander; Meves). In some cases, however, it resides in, or arises from, the nucleus (Brauer; spermatogenesis of _Ascaris_, var. _univalens_). This indifferent nuclear or cytoplasmic position for the centrosome is paralleled by the attraction sphere or homologue of the centrosome in many Protozoa. Thus in many forms, e.g. _Euglena_ (Keuten), it lies within the nucleus, while in other forms, e.g. _Noctiluca_ (Ishikawa, 1894, 1898; Calkins, 1898) and _Paramoeba_ (F. Schaudinn, 1896), it lies in the cytoplasm, while in _Tetramitus_ it coexists with a "distributed" nucleus. In the Heliozoa conditions are exceptionally interesting; not only is the centrosome--here resembling in appearance that of the higher forms--permanently visible and extranuclear, lying at the centre of the radiations characteristic of these forms, but there is the strongest possible evidence for its formation _de novo_. For Schaudinn has shown in _Acanthocystis_ that, in the formation of the swarm spores, the nucleus divides amitotically, the centrosome remaining visible and unchanged at the centre of the radiating processes. Yet a centrosome appears later in the nucleus of the swarm spores and migrates into the cytoplasm. The experiments of T. H. Morgan and E. B. Wilson, in which numerous centrosomes and asters ("cytasters") are caused to appear in unfertilized sea-urchin eggs by a brief immersion in a 13% solution of magnesium chloride in sea-water,[29] as also the possibility in many cases that even in normal fertilization the cleavage centrosomes may arise _de novo_,[30] make it no longer possible to regard the centrosome as a permanent cell-structure.

_Significance of Mitosis._--Whatever may be the nature of the chemico-physical changes occurring during cell-division, of which the achromatic spindle and astral rays are the visible expression, it is certain that the whole of this complicated process has for its function, not the division of the chromatin, for that has already occurred on the spireme thread or even earlier, but the distribution of the divided chromatin granules to the two daughter nuclei. It is indeed usually assumed that the mitotic mechanism is not merely for the distribution, but for the _equal_ distribution, of the sister granules to the two daughter nuclei. The conspicuous part the chromatin is seen to play in the whole mechanism of heredity--in maturation, fertilization and development--indicating as it does that the chromatin is the chief, if not the only, bearer of the specific qualities of the organism, sufficiently clearly emphasizes the importance of the equal distribution of this substance between the daughter cells at successive cell-divisions. There are, however, serious objections to the interpretation of mitosis as an adaptation to ensure this equal distribution of the chromatin. Not only does the occurrence of amitosis show that the mitotic mechanism is not essential for either nuclear or cytoplasmic division, but direct division may occur[31] in the life-history of the germ cells, the very point at which it should not occur had mitosis the significance usually attached to it. On the other hand, the most elaborate mitosis occurs in cell-tissues (e.g. skin of salamander larva) which can take no possible share in the reproduction of the species. Moreover, we have no reason for supposing that the division of the chromatin in amitosis is not as meristic, and its subsequent distribution as equal, as is so visibly the case in mitosis.[32] It is necessary, therefore, to seek for some other explanation of the elaborate mechanism of mitosis than that which assumes it necessary for the equal distribution of the divided chromatin granules. The present writer believes the true explanation to be found in that great economic law of nature, "division of labour." The same economy which, working under the control of natural selection, has produced the complexly differentiated tissues of the higher metazoa, which has led to the sexual differentiation between the conjugating gametes and thus to the sexual differentiation of the parents, has resulted in the production of mitosis. Only here the economy finds expression in division of labour, not in space, but in time. The work of the self-propagating chromatin granules is so ordered that periods of undisturbed metabolic activity alternate with periods of reproductive activity. The brief space of time occupied by the latter process has necessitated a more elaborate specialization of the forces--whatever their nature--controlling cell-division; a specialization which has resulted, just as a similar specialization in so many other cases has resulted, in a visible differentiation of the cell-protoplasm. This explanation is in harmony with the occurrence of typical mitosis in active tissue cells on the one hand, and of amitosis in the relatively quiescent primary germ cells on the other.

_Individuality of the Chromosomes._--The most striking feature in the behaviour of the chromatin in mitosis is its resolution, at each division, into a--for any particular species--constant number of chromosomes. This constant recurrence of the specific number of chromosomes at every cell-division is capable of explanation in two radically different ways. One explanation assumes for the organism a specific peculiarity determining the segmentation of the spireme thread into a definite number of segments (Delage, 1899 and 1901).[33] The other regards chromosomes as independent units of the cell, retaining their identity between successive cell-divisions. The latter "Individualitats Hypothese" was originally put forward by Theodor Boveri in 1887 as a result of C. Rabl's observation (1885) that in epidermal cells of the salamander larva the chromosomes reappear in the mitosis of the daughter cells with the same arrangement as they possessed in the prophase of the mother cell--the angles of the U-shaped chromosomes being all directed towards one pole (Rabl's "Poleseite") of the nucleus. In the formation of the "resting" nucleus, the chromatin, becoming metabolically active, flows out on to the linin reticulum, all trace of the chromosomes being for the time lost. In _Ascaris_, Boveri (1888) obtained similar but still more striking results. The thickened ends of the four elongated chromosomes cause projections on the nuclear surface throughout the resting period, and the ends of the reappearing chromosomes always coincided with these protuberances; cf. also Sutton (1902) on locust spermatagonia. Moreover, the arrangement of the chromosomes must follow one of three well-marked groupings, and this is determined for each individual in the cleavage spindle of the egg and maintained throughout later development (fig. 8).

FIG. 8.--Preparation for Mitosis. a, Nucleus of "1/2 blastomere" of _Ascaris megalocephala bivalens_ in resting condition; b and c, nuclei from sister 1/2 blastomeres in preparation for mitosis.]

In the same worm (var. _univalens_) Boveri (1888 and 1899) found that occasional abnormalities in maturation resulted in the suppression of the first polar body and the inclusion of its chromosomes in the second maturation spindle; the egg-nucleus at the time of fertilization thus having two chromosomes instead of one, while the spermatozoon nucleus has only one. Three chromosomes instead of two reappear in subsequent divisions. Boveri's "Individualitats Hypothese" received striking support from the work of Herla (1893), L. R. Zoja (1895) and O. zur Strassen (1898). Herla and Zoja showed that if the egg of _Ascaris megalocephala_ (var. _bivalens_), which possesses two chromosomes, be fertilized with the spermatozoon of var. _univalens_, in which the germ cell has only one chromosome and that smaller than either of the two in the other variety, three chromosomes reappear, two large and one small, in the cleavage divisions of the resulting hybrid embryo. Zur Strassen's observations on the giant embryos of _Ascaris_ also support Boveri's theory. These embryos arise by the fusion of eggs, either before or after fertilization. The number of chromosomes in the subsequent cleavage-figures is proportional to the number of nuclei that have fused together. Similar results are given by Boveri's (1893-1895) and T. H. Morgan's (1895) experiments on the fertilization of enucleated sea-urchin egg-fragments; all the nuclei of the resulting embryo having only half the number of chromosomes characteristic of the species (e.g. in _Echinus_ 9 instead of 18). All the above facts point to the conclusion that, as Boveri expressed it in his _Grundgesetz der Zahlenkonstanz_ (1888), "the number of chromosomes arising from a resting nucleus is solely dependent on the number which originally entered into its composition."[34]

_Boveri's Law of Proportional Nuclear Growth._--The chromatin in the nucleus is exactly halved at every cell-division. As the bulk of the chromatin remains constant from one cell-generation to another, it must double its bulk between successive divisions. That this proportional growth of the chromatin is dependent solely on the chromatin mass, and not on that of the cell, is very clearly indicated by cases where the normal chromatin mass has been artificially increased or reduced,[35] the chromatin in either case doubling its bulk between successive cell-divisions, and neither the mass of the chromatin nor the number of the chromosomes undergoing any readjustment. By double or partial fertilization, different regions in the same embryo may show nuclei of different sizes (Boveri). We must therefore distinguish in the cell between "young" and "adult" chromatin. In other words the chromatin must be regarded as being composed of individual units, each with a definite constant structure and maximum growth (Boveri, 1904). This conclusion is strongly suggested, not only by the evidence in favour of the individuality of the chromosomes considered above, but also by the independent reproductive activity of the chromatin granules in the prophase of mitosis.

FIG. 9.--Preparation for Mitosis. a, Spermatogonium of _Brachystola magna_ with resting nucleus; b, Same with prophase for mitosis. (After Sutton.)]

_Differentiation among the Chromosomes._--If we grant the assumption of a persistent individuality for the chromosomes, then it becomes possible to consider whether in one and the same nucleus these structures may not take varying parts in controlling the cell's activity in development and in inheritance. Such a differentiation among the chromosomes would be due to independent ancestry rather than to the economy resulting from a division of labour; nevertheless a division of labour of a sort would be the result of this gradual divergence of the chromosomes from one another, and we might therefore expect that, in some cases at least, a _morphological_ would accompany the _physiological_ differentiation. Examples of such a morphological differentiation do indeed occur in the "accessory" chromosomes first described by H. Henking (1891) for the spermatogonia of _Pyrrhocoris_, and since described for numerous other insects, Arachnids and Myriapods. W. Sutton's work on the spermatogenesis of _Brachystola magna_ is of especial interest in this connexion. Not only does the "accessory chromosome" in this insect form a resting nucleus independent, and obviously physiologically differentiated from that formed from the remaining chromosomes (fig. 9, a), but the latter are themselves differentiated by size, there being one pair of chromosomes of each size (fig. 9, b), a point of considerable interest when we remember that half the chromosomes in each cell are necessarily derived from each parent.[36]

Although this morphological differentiation among the chromosomes is undoubtedly to be regarded as indicating a corresponding physiological differentiation, it by no means follows that the latter need always, or even generally, be accompanied by the former. Since, however, the specific characters of the organism must be due to the combined activity of _all_ the chromosomes, any physiological differentiation among the latter should result in abnormal development if the full complement of chromosomes be not present.[37] Boveri,[38] utilizing Herbst's method[39] for separating echinoderm blastomeres, has interpreted in this manner the abnormal development which H. Driesch[40] found almost invariably to follow the double fertilization of the sea-urchin egg. In such eggs the first cleavage spindle is four-poled. The chromosomes are half again as numerous as in normally fertilized eggs (54 instead of 36), but each is only divided once, so that in the distribution of the resulting 108 chromosomes the four daughter nuclei receive each only 27 instead of 36 (assuming the distribution to be fairly equal, which is by no means usually the case in four-poled mitosis). Driesch had already (1900) shown that any one of the first four blastomeres of a normally fertilized egg will, if isolated, develop normally. Boveri found that in the case of the doubly fertilized egg the isolated "1/4" blastomeres develop very variously, a variability only to be accounted for by their varying chromosome equipment. Occasionally a three-poled instead of a four-poled figure resulted from double fertilization. In such cases Driesch found, as we should expect from Boveri's interpretation, that the percentage of approximately normal larvae was considerably greater; for not only would the chances of an equal distribution of the chromosomes be much greater, but the number received by each of the three daughter cells would approximate to, or even equal, the normal.

_Reduction._--In all the Metazoa the prevailing, and in the higher forms the only, method of reproduction is by the union (conjugation) of two "sexually" differentiated germ-cells or "gametes"; a small motile "microgamete" or spermatozoon and a large yolk-laden "macrogamete" or ovum (see Reproduction). This differentiation between the germ-cells is another example of the advantages of division of labour; for while the onus of bringing about the union of the germ-cells is thrown entirely on the spermatozoon, the egg devotes itself to the accumulation of food-material (yolk) for the subsequent use of the developing embryo. Far more yolk is thus secreted than would be possible by the combined efforts of both the germ-cells had each of these at the same time to preserve its motility. The fundamental physiological difference which this division of labour has produced in the germ-cells is reflected on to the general metabolism of the parents and underlies the sexual differentiation of the latter.[41] Beyond this, however, sexual differentiation does not go. The two germ nuclei which enter into the formation of the first mitotic figure of the developing egg are not only physiologically equivalent, but, at the time of their union in the egg, are usually morphologically identical.[42] The essence of fertilization is, therefore, the union of two germ nuclei only differing from one another in that they are derived from separate individuals.[43] Since the number of chromosomes appearing in mitosis is solely dependent on the number which originally entered into the composition of the nucleus (Boveri's Law of Chromosome-Constancy), it follows that, in the mitotic figures of the developing embryo, the chromosomes will be half maternal, half paternal in origin;[44] the germ nuclei thus necessarily possessing only half the number of chromosomes characteristic of the ordinary tissue cells of species, i.e. the somatic number.[45] The manner in which this "reduction" in the number of chromosomes in the germ-cells is brought about, and the significance to be attached to the process, constitute the most hotly debated questions in cytology. In all the metazoa the phenomenon of reduction is associated with the two last and, usually, rapidly succeeding "maturation" divisions by which the definitive germ-cells--ova or spermatozoa--are produced.[46]

Assuming the persistent individuality of the chromosomes, then there are only three conceivable methods by which this numerical reduction can be brought about (Boveri, 1904, p. 60). (1) One-half the chromosomes degenerate. (2) The chromosomes are distributed entire, half to one daughter cell, half to the other (reducing division of Weismann, 1887). (3) The chromosomes fuse in pairs (_Conjugation of the Chromosomes_, Boveri, 1892). The first possibility--that of an actual degeneration of a part of the chromatin originally suggested by van Beneden and adopted by August Weismann, Boveri and others, has been long abandoned, and a steadily increasing bulk of evidence is tending to prove the general, if not universal, occurrence of the second method--the distribution between the daughter cells of undivided chromosomes. The occurrence of such a "reducing division" was postulated on theoretical grounds by Weismann (1887)[47] and by Boveri (1888); by the former as a result of his adoption of de Vries's hypothesis of self-propagating and qualitatively varying units for the chromatin; by the latter in relation to his theory of chromosome individuality. The actual occurrence of this reducing division was first demonstrated by Henking (1891) for _Pyrrhocoris_, and afterwards by Hacker, vom Rath and many others, but especially by Ruckert (1894) for _Cyclops_ (fig. 10). In this latter type the chromatin of the oocyte, as this prepares for the first maturation division, resolves itself into 12 (instead of 24) longitudinally split chromosomes (fig. 10, a). As these continue to thicken and contract a transverse fission appears (fig. 10, c). This is to be regarded as a belated segmentation of the spireme thread, and shows that the reduction so far is only a "pseudo-reduction" (Ruckert), the chromosomes being really all present but temporally united in pairs, i.e. "bivalent" (Hacker). A striking confirmation of this interpretation is provided by Korschelt's description of reduction in the annelid _Ophryotrocha_. In this type the full somatic number of split chromosomes (here only four) appears, and these secondarily associate end to end in pairs, thus forming split "diads" (i.e. tetrads), in every way similar to those described by Ruckert for _Cyclops_. In the latter type, at the first maturation division, the sister diads are separated from one another, an "equating" division thus taking place. At the second division the diads are resolved into their constituent parts, and the "univalent" chromosomes are distributed to the daughter cells (reducing division). A similar process has since been described for numerous other types (e.g. various arthropods, Hacker, 1895-1898; vom Rath, 1895; and by Sutton for _Brachystola_, 1902-1903). In _Ophryotrocha_, as in _Pyrrhocoris_ (Henking), _Anasa_ (Paulmeir), _Peripatus_ (Montgomery), &c., reduction occurs at the first maturation division ("pre-reduction" of Korschelt and Heider, 1900), instead of at the second division (post-reduction) as in most Copepods and Orthoptera. In many cases the tetrads (i.e. split chromosomes associated in pairs) have the form of rings, the genesis of which was first clearly determined by vom Rath (1892) in the mole cricket _Gryllotalpa_ (fig. 11). In this form the sister diads remain united by their ends but widely separate in the middle (fig. 11, b). As in _Cyclops_, the belated transverse segmentation appears as the condensation of the chromatin proceeds (fig. 11, d), but the symmetrical tetrads which this process here produces make it impossible to determine at which of the two divisions reduction is effected. An essentially similar ring formation occurs in _Enchaeta_ and _Calanus_ (vom Rath), and in the Copepods _Heterocope_ and Diaptomus (Ruckert), and in other types.[48]

FIG. 10.--Maturation Divisions. a-d, Formation of the tetrads in _Cyclops_. (After Ruckert.) e, 1st maturation division; separation of the bivalent sister chromosomes. f, 2nd maturation division; distribution of the univalent chromosomes.]

FIG. 11.--Maturation Divisions. Origin of the tetrads by ring formation in the spermatogenesis of the mole-cricket (_Gryllotalpa_) (vom Rath). a, Primary spermatocyte with six split, bivalent chromosomes. b and c, Split has opened out. d, Concentration of the chromatin has made visible the belated transverse division. e and f, Grouping of the completed tetrads in the equatorial plate of the first maturation division.]

FIG. 12.--Heterotypical Mitosis. (Schematic, after Flemming.)]

All the above cases, in which the reduction is effected by the distribution of entire chromosomes at one or other of the maturation divisions, may be grouped together as "pseudomitotic" (Hacker, and Korschelt & Heider). In sharp contrast to the pseudomitotic method is the "Eumitotic" method, in which the chromosomes are longitudinally divided at both divisions. Such a method not only robs the process of any "reducing" value in Weismann's sense, but is in serious conflict with the chromosome-individuality hypothesis. Nevertheless it is in this sense that Boveri (1881) and van Beneden (1883-1887) described the maturation of the egg, and at a later period Brauer (1893) that of the spermatozoon, in _Ascaris_. In each case the tetrads are formed by the double longitudinal splitting of the chromosomes, the latter appearing in the prophase in the reduced number. Not only was the eumitotic method of _Ascaris_ the first method to be described, but the descriptions are fully equal in point of clearness to that of Hertwig for the pseudomitotic maturation of _Cyclops_.[49] A similar eumitotic maturation has been described for other types also, e.g. _Sagitta_ and the Heteropods, but nowhere more frequently than in the Vertebrates among animals and the Phanerogams among plants. In these two latter groups the chromosomes of the reducing division only rarely have a ring form comparable to that seen in _Gryllotalpa_, &c. When such rings do occur their genesis is very obscure, and at no time do they present the appearance of "tetrads." It is the characteristic appearance these looped chromosomes give to the first maturation division in many Vertebrates, and especially in the Amphibia (fig. 12), that originally led Flemming (1887) to term this type of mitosis "heterotypical"; the second division, lacking this peculiar appearance, being distinguished as "homotypical." Until quite recently these looped chromosomes of the heterotypical mitosis of Vertebrates (and plants) were described as arising by the opening out of longitudinally split chromosomes, exactly as this occurs in the early prophase of the maturation divisions in such types as _Gryllotalpa_, _Diaptomus_, &c. In the heterotype mitosis, however, no transverse segmentation appears, and the halves of the rings, as they separate in the first division, show an obvious longitudinal split in preparation for the second division.[50] Both divisions were thus interpreted as equating divisions.[51] The more recent works of Farmer and Moore (1903-1905), Montgomery (1903, Amphibia), and (for plants) Strasburger (1903-1904) have shown, however, that even for the higher plants and animals, a reducing division in Weismann's sense occurs in an essentially similar manner to that so convincingly described by Ruckert, vom Rath and others, for Invertebrate types. For the chromosomes of the heterotype mitosis arise by the looping round, not opening out, of the bivalent chromosomes. The first division is thus a reducing division, while the split appearing in the anaphase of the heterotype and presumably reappearing in the prophase of the homotype is the original split of the spireme thread.

The widespread, if not universal, formation of tetrads, i.e. the temporary union in pairs of split chromosomes, in reduction, and the relation this latter process always bears to _two_ rapidly succeeding maturation divisions--those completing the gametogenic cycle in animals and terminating the sporophytic generation in plants,--has received a suggestive explanation at the hands of Boveri (1904). The growth of the chromatin is an indispensable prelude to its reproduction (Boveri's Law of Proportional Growth). The chromatin is therefore incapable of undergoing reproductive fission in two successive mitotic divisions when these are not separated by a resting (i.e. growth) period. In addition to this, the "bipolar" condition of the adult chromosomes, which determines its mode of attachment to mantle fibres from _both_ poles of the spindle, is not possessed by the unripe chromatin. The undivided, i.e. unripe, chromosomes are therefore incapable of utilizing the mitotic mechanism for such a transverse fission as Weismann originally postulated. The difficulty is, however, at once overcome if the unripe chromosomes are associated in pairs in the equatorial plate, for the bivalent chromosomes so produced are bipolar just as are the adult (i.e. split) chromosomes in the ordinary and homotype mitosis.[52]

_Synopsis_ ([Greek: synaptein], to fuse together).--During the prophase of the reducing or heterotype divisions the whole of the chromatin becomes temporarily massed together at one pole of the nucleus (Moore, 1896, for Elasmobranchs). Montgomery (1901) has suggested that this is to facilitate the temporary union in pairs, or "conjugation" of homologous paternal and maternal chromosomes. In _Ascaris megalocephala_ var. _univalens_, where the somatic number is only two, the association must necessarily be between homologous chromosomes. The assumption that this "selective pairing" of equivalent chromosomes is universal is supported by the behaviour of the "Heterochromosomes" (Montgomery) of the Hemiptera. These chromosomes, distinguished by their size, are paired before, and single after, the "pseudo-reduction" has taken place. Even more convincing is Sutton's account of reduction in _Brachystola_ already referred to.[53] Boveri (1904) has suggested that this temporary association of the chromosomes--presumably facilitated by the synapsis--has a much deeper meaning than to ensure their correct distribution between the daughter nuclei in the heterotype mitosis; the associated chromosomes exchanging material in a manner analogous to conjugation in _Paramoecium_.[54]

_Present Position of the Cell-theory._--Since the time of Schleiden and Schwann a wealth of evidence has accumulated in support of the "cell-theory"--the theory which regards the cell as the unit of organic structure. "The organism consists morphologically, of cells, and subsists, physiologically, by means of the 'reciprocal action' of the cells,"--this was the cell standpoint of Schleiden and Schwann, and it is no exaggeration to say that this same conception has dominated the cell-theory almost to the present day.[55] The frequently striking correlation between cell-division and cell-differentiation in development has caused this process to be regarded as dependent on cell-division, while a wholly exaggerated importance has been attached to the distinction between "unicellular" and "multicellular" organisms--between "intercellular" and "intracellular" organs. The influence of the "cells" upon one another, the subordination of the cell's growth, division and differentiation, to the requirements of the whole organism--seen in normal growth, but nowhere more strikingly than in development and regeneration,--is, however, very difficult of explanation in terms of the cell-theory as this was, until quite recently, generally understood. The very elaborate regional differentiation of the protoplasm often seen in the Protozoa sufficiently indicate that multicellular structure is no essential condition for complex regional differentiation. That the regional differentiation of the protoplasm in the Metazoa should usually correspond with cell-limits is scarcely surprising. Nor is it to be wondered at that, with so convenient a mechanism for segregation to hand as cell-division, the progressive differentiation seen during development should often appear to go hand in hand with this process. In recent years, however, evidence has been steadily accumulating to show that this association between cell-division and regional differentiation of the protoplasm in development is a casual one--as casual, and as natural, as the correspondence between cell limits and regional differentiation in the formed tissues. The fact that the regional differentiation may be foreshadowed in the egg before cleavage begins,[56]--that as Driesch has shown, the mode of cleavage may be artificially altered without affecting the ultimate organization of the embryo,--and many other similar observations, tend to emphasize the importance of the "organism" standpoint (C. O. Whitman, 1903, p. 642) in contradistinction to the widely prevalent "cell" standpoint. The occurrence of syncytial organs and organisms, and the increasing frequency with which protoplasmic continuity is being demonstrated between all kinds of cells, are facts tending in the same direction. In the plant kingdom the growth of the _mass_ has been recognized as the primary factor in development;[57] _die Pflanze bildet Zellen, nicht die Zelle bildet Pflanzen_ (de Bary). For the animal kingdom this "Inadequacy of the Cell-Theory of Development" has been maintained amongst others by Whitman,[58] and by Adam Sedgwick.[59] The latter author, mainly as the result of work on the development of _Peripatus_ and of Elasmobranch embryos, regards the developing embryo as a continuous protoplasmic reticulum, for the nuclei of which the limiting epithelial layers constitute as it were a breeding ground. Differentiation is a regional specialization of this nucleated meshwork, and is not to be regarded as the result of the proliferation and subsequent specialization of cells predestined by cleavage for this end.

It is possible to suggest a mechanico-physical explanation of multicellular structure which will deprive the cell of much of its assumed significance as a unit of organization. The fact that surface area becomes relatively less extensive as bulk increases would alone set a limit to the size of "unicellular" organisms; for not only is there a constant reaction between nucleus and cytoplasm through the nuclear membrane, but the surface of the cell serves both for the intake of food and the elimination of waste material. In addition to the limit thus imposed upon the cytoplasmic area which can be effectually controlled by the nucleus, and the necessity for a minimum surface area to the protoplasmic mass, the advantages of the more or less complete subdivision of the living substance into--as far as their metabolism is concerned--semi-autonomous units, is indicated by the mechanical support derived from the specialized cell walls and turgescent cells of the plant, and the intercellular secretions of the animal tissues. It is more than possible that these two conditions--i.e. surface area for diffusion, and mechanical support--are alone responsible for the _origin_ of multicellular structure, and that the sharply defined character this now so generally possesses has been secondarily acquired as a result of the facilities it undoubtedly offers for regional specialization in the protoplasmic mass.

BIBLIOGRAPHY.--The special literature of cytology has grown to large
dimensions. The following are the more important text-books and papers
of general interest: E. B. Wilson, _The Cell in Development and
Inheritance_ (2nd ed., 1900); A. Gurwitsch, _Morphologie und Biologie
der Zelle_ (Jena, 1904); O. Hertwig, _Allgemeine Biologie_ (Jena,
1906); Korschelt and Heider, _Lehrbuch der vergl.
Entwicklungsgeschichte der wirbellosen Tiere_, Allgem. Teil, "The Germ
Cells and Experimental Embryology" (Jena, 1903); Whitman, "The
Inadequacy of the Cell Theory of Development," _Journ. Morph._ viii.,
1893; Adam Sedgwick, "On the Inadequacy of the Cellular Theory of
Development," _Quart. Journ. Micro. Science_, xxxvii.; G. C. Bourne,
"A Criticism of the Cell Theory" (an answer to Sedgwick's paper),
_Quart. Journ. Micro. Science_, xxxviii.; Th. Boveri, "Befruchtung,"
_Merkel-Bonnets Ergebnisse der Anat. u. Entwicklungsgesch._ Bd. i.
(1892), _Das Problem der Befruchtung_ (Jena, 1902), _Ergebnisse uber
die Konstitution der chromatischen Substanz des Zellkerns_ (Jena,
1904); J. Ruckert, "Die Chromatinreduktion bei der Reifung der
Sexualzellen," _Merkel-Bonnets Ergebnisse_, Bd. iii. (1894); V.
Hacker, "Die Reifungserscheinungen," _Ergebn. Anat. u.
Entwicklungsgesch._ Bd. viii. (1898); F. Meves, "Zellteilung,"
_Merkel-Bonnets Ergebnisse_, Bd. viii. (1898, 1899); W. Waldeyer, "Die
Geschlechtszellen," in O. Hertwig's _Handbuch der vergleich. u.
experiment. Entwicklungslehre d. Wirbeltiere_ (1901, 1903).
(G. C. C.)

FOOTNOTES:

[1] _Allgemeine Physiologie_, p. 53 (1895).

[2] _Vom inwendigen Bau der Gewachse_ (1806).

[3] The Chromoplastids of the vegetable cell come under a different
category of cell-inclusions; see PLANTS: _Cytology_.

[4] Cf. Pfeffer's classical experiments on the physiological
significance of cell-continuity in plant tissues (_Uber den Einfluss
des Zellkerns auf die Bildung der Zellhaut_, 1896). The recent work
in physiology on the influence substances secreted by certain tissues
and circulating in the blood-stream exert upon other and widely
different tissues, should not be lost sight of in this connexion.

[5] The influence this protoplasmic continuity may have upon our
conception of the cell as a unit of organization is referred to below
(_Present Position of the Cell-theory_).

[6] A term (from [Greek: karyon], kernel) suggested by Flemming to
replace Strasburger's hybrid term "nucleoplasm" (1882). The earlier
workers, e.g. Leydig, Schultze, Brucke, de Bary, &c., restricted the
term protoplasm to the cell-body--the "Cytoplasm" of Strasburger, an
example still followed by O. Hertwig.

[7] From _linum_, a thread, Schwarz, 1887.

[8] From [Greek: chroma], colour, Flemming, 1879.

[9] The formation of pseudopodia and accompanying changes in form of
_Amoeba_ were observed as early as 1755 by Raesel von Rosenhof, who
named it on this account the "little Proteus."

[10] "Sur les rapports des cils vibratiles avec les centrosomes,"
_Archives d'anatomie microscopique_ (1898).

[11] "Uber Zentralkorper in mannlichen Geschlechtszellen von
Schmetterlingen" (Anat. Anz. Bd. xiv., 1897). Cf. also the papers of
Lenhossek (_Uber Flimmerzellen_, 1898), Karl Peter (_Das Zentrum fur
die Flimm- und Giesselbewegung_, 1899) and Verworn (_Studien zur
Physiologie der Flimmerbewegung_, 1899).

[12] Cf., however, the present writer's interpretation of this
structure in the oocyte of _Antedon_. _Phil. Trans. Royal Soc._
(1906), B. 249.

[13] Claude Bernard expressed the same conclusion in 1885. Rejecting
both the view that vital phenomena were identical with
chemico-physical phenomena, and that which regarded them as totally
distinct, he suggested a third point of view: "l'element ultime du
phenomene est physique; l'arrangement est vital."

[14] Many forms of response to stimulus involve no visible
specialization, e.g. positive and negative heliotropism,
chemiotropism, geotropism, &c., seen more especially in plants, but
occurring also in the animal kingdom.

[15] Prominent among these are: Schleiden (1873), Fol (1873-1877),
Auerbach (1874), Butschli (1876), Strasburger (1875-1888), O. Hertwig
(1875-1890), R. Hertwig (1875-1877); Flemming (1879-1891), van
Beneden (1883-1887), Rabl (1889), Boveri (1887-1903).

[16] This distinction between the chromatic and achromatic portions
of the mitotic figure is due to Flemming.

[17] The genesis of the spireme thread was first described by E. G.
Balbiani in 1876.

[18] "Recherches sur la maturation de l'oeuf, la fecondation et la
division cellulaire" (_Archives de biologie_, vol. iv.).

[19] First discovered by Flemming in 1879 and confirmed by Retzius in
1881.

[20] The discovery by Hermann of the central spindle first clearly
showed that two kinds of fibres must be recognized in the mitotic
figure. Those of the central spindle correspond to the continuous
spindle fibres of Flemming (1891) and Strasburger (1884), and the
mantle fibres, i.e. half-spindle or _Polstrahlen_, of van Beneden
(1887) and Boveri (1889-1890).

[21] Planter, Watase, Griffen and others.

[22] e.g. _Euglypha_ (Schewiakoff, 1888), Infusoria (R. Hertwig,
1898). So also Korschelt for _Ophryotrocha_, and many other cases.

[23] e.g. Bauer, spermatogenic cells of _Ascaris univalens_.

[24] Cf. also Watase, Solger and Zimmermann.

[25] This term is due to Boveri (_Zellenstudien_, ii., 1888, p. 68;
_Jen. Zeit._ xxii.), but it was intended by him to include the region
of modified cytoplasm or "centrosphere" often enclosing the
centrosome proper, i.e. "centriole" of Boveri.

[26] For outline of fertilization see article REPRODUCTION.

[27] e.g. lymph and various epithelial and connective tissue cells of
salamander larva (Flemming, 1891; Heidenhain, 1892); pigment cells of
fishes (Solger, 1891); red blood corpuscles (Heidenhain, Eisen,
1897); and numerous other cases.

[28] For an interesting development of this subject see Watase
(1894). This author not only identifies the centrosome with the
structures seen in lymph cells, &c., but compares it to the basal
granules of ciliated cells and to the varicose swellings on the
sarcostyles of striped muscle cells!

[29] The force of this evidence is admitted by Boveri himself. Meves,
however, maintains the possibility that the numerous centrosomes
appearing in the egg arise by the rapid fragmentation of a centrosome
already present.

[30] Cf. especially the behaviour of the centrosomes in the
fertilization of the egg of _Pleurophyllidia_ (MacFarland, 1897) and
that of _Cerebratulus_ (Coe, 1901). Not only may the sperm
centrosomes totally disappear before reaching the egg-nucleus, but in
the latter type the definitive centrosomes appear while the last
traces of the sperm asters are still visible.

[31] e.g. Meves; Spermatagonia of Salamandra.

[32] Cf. especially the artificial production of amitosis in
_Spirogyra_; W. Pfeffer, 1899.

[33] Cf. Boveri, 1904, p. 13. (For Boveri's criticism of Delage's
views, cf. Boveri, 1901 and 1902.)

[34] It should, however, be noted that the assumption that a
particular group of characters remains always associated in a
particular chromosome is one that is very difficult to reconcile with
the mode of inheritance of Mendelian pairs of characters in the case
of organisms with a relatively small chromosome number.

[35] Boveri (1902), "Fertilization of enucleated _Echinus_-egg
fragments," and M. Boveri (1903); by shaking the egg shortly after
fertilization the sperm centrosome is prevented from dividing, and a
monaster instead of a diaster results, the divided chromosomes
remaining in the one nucleus.

[36] Cf. especially in this connexion Hacker's paper _Uber die
Schicksale der elterlichen und grosselterlichen Kernanteile_ (1902).

[37] Each nucleus contains a duplicate set of chromosomes, the one of
maternal, the other of paternal origin, and either of these sets
alone suffices for development. This is clearly shown by the
experiments of Loeb (1899) and Wilson (1901) on the artificial
parthenogenesis of the sea-urchin egg; and those of O. Hertwig (1889
and 1895), Delage (1899) and Winkler (1901), on the fertilization of
enucleated Echinoderm eggs (_Merogony_, Delage). The fact that in
some forms, e.g. _Ascaris megalocephala_ var. _univalens_, only one
chromosome is derived from each parent, originally led Boveri to
conclude that _all_ chromosomes must necessarily be physiologically
equivalent.

[38] _Uber mehrpolige Mitosen als Mittel zur Analyse des Zellkerns_
(1902).

[39] _Uber das Auseinandergehen von Furchungs- und Gewebezellen in
kalkfreien Medium_ (1900).

[40] "Entwicklungsmechanische Studien V." (_Zeit. fur wiss. Zool._,
Bd. lv., 1892).

[41] See Geddes and Thomson, _Sex_, esp. pp. 127, 137 and 139.

[42] The equivalence of the germ nuclei in development is shown by
the experiments on the fertilization of enucleated eggs and
artificial parthenogenesis already referred to.

[43] O. Hertwig, 1873; but esp. van Beneden, 1883.

[44] Hacker, "Uber die Selbststandigkeit der vaterlichen und
mutterlichen Kernbestandteile," _Arch. f. mikr. Anat._ Bd. xlvi.
(1896).

[45] First discovered by van Beneden (1883, 1887) for the egg of
_Ascaris_.

[46] In the case of the egg the whole of the yolk stored by the
"oocyte" (cell-generation immediately preceding the maturation
divisions) is handed on to only one of the four resulting cells--an
obvious economy. The three yolkless cells are necessarily
functionless--abortive ova--and are known as the "polar bodies"
(Hertwig). In spermatogenesis the maturation divisions, though
bearing the same relation to reduction as in oogenesis (Platner,
1889; O. Hertwig, 1890), give rise to four functional germ-cells. The
explanation of sexual differentiation given above, and that of polar
body formation given here, render it needless to do more than mention
the theories of Mimot (1877), van Beneden (1883) and others, by which
"maturation" was regarded as removing the "male" element from the
otherwise "hermaphrodite" egg.

[47] Weismann postulated a transverse division of the chromosomes,
not a distribution of entire chromosomes; but the result as far as
the reduction in the number of hereditary qualities goes is the same.
The inability of the mitotic mechanism to effect the transverse
division of unsplit chromosomes is pointed out by Boveri (1904).

[48] For an exhaustive account of reduction in Invertebrates see
Korschelt and Heider, _Entwicklungsgeschichte_, Allgem. Teil ii.
(Jena, 1903).

[49] Nevertheless the possibility of a pseudomitotic interpretation
of maturation in _Ascaris_ also has been maintained by O. Hertwig
(1890), p. 277, Carnoy and Boveri (1904).

[50] The partial or even complete reconstruction of the nucleus
between the heterotype and homotype division in Vertebrates makes it
difficult to determine the identity of the split seen in the anaphase
of the heterotype with that reappearing in the prophase of the
homotype.

[51] e.g. Moore, 1895 (_Scyllium_); Flemming, 1897; Carnoy and
Lebrun, 1899 (_Amphibia_); McGregor, 1899; Lenhossek, 1898 (mammals),
and many others. So also for plants: Strasburger and Mottier, 1897;
Dixon, 1896; Sargant, 1896-1897; Farmer and Moore, 1895; Gregoire,
1899; Guignard, 1899, &c.

[52] H. Henking (1899), T. Montgomery (1898) and F. C. Paulmeir
(1899) describe the diverging bivalent halves of the tetrad as being
united each by _two_ fibres with the corresponding spindle pole. At
the next division, at which the diad is resolved into its constituent
univalent chromosomes, the daughter chromosomes are attached to the
spindle pole each by only one fibre; the two fibres now passing to
opposite poles of the spindle being the same fibres which, in the
preceding mitosis, were attached to one and the same pole.

[53] Reference may be here made to Rosenberg's description (1904) of
the heterotype mitosis in _Drosera_ hybrids. In the one parent (_D.
rotundifolia_) the somatic number is 20, in the other (_D.
longifolia_) 10; while the hybrid itself has a somatic number of 30.
The reduced number in the hybrid, however, is not 15 but 20. Of these
10 are large and 10 small, the latter presumably representing the
supernumerary, and hence unpaired, chromosomes of the _D.
rotundifolia_ parent.

[54] In their 1905 paper J. B. Farmer and J. E. S. Moore describe two
successive synaptic stages (e.g. Elasmobranchs), the first during the
contraction of the spireme thread, the second during the looping up
of the bivalent segments. (In this paper the authors suggest the term
"Meiosis" or "Meiotic phase" for the nuclear changes accompanying the
two maturation divisions in plants and animals ([Greek: meiosis],
reduction).

[55] Whitman, _Jour. Morph._, 1903.

[56] This "Precocious segregation" (Lankester, 1877) is well seen in
the eggs of many Ctenophorae, Annelids, Gastropods and Nematodes. See
the papers by Lillie (1901), Conklin (1902), &c., and especially
Wilson on "Dentalium," _Journ. of Exp. Zool._, No. 1, 1904.

[57] Hofmeister, de Bary, Sachs, &c.

[58] _Loc. cit._

[59] _Quart. Journ. Micro. Science_, 1894, vol. xxxvii.

CYZICENUS, the architectural term given by Vitruvius to the large hall, used by the Greeks, which faced the north, with a prospect towards the gardens; the windows of this hall opened down to the ground, so that the green verdure could be seen by those lying on the couches.

CYZICUS, an ancient town of Mysia in Asia Minor, situated on the shoreward side of the present peninsula of Kapu-Dagh (Arctonnesus), which is said to have been originally an island in the Sea of Marmora, and to have been artificially connected with the mainland in historic times. It was, according to tradition, occupied by Thessalian settlers at the coming of the Argonauts, and in 756 B.C. the town was founded by Greeks from Miletus. Owing to its advantageous position it speedily acquired commercial importance, and the gold _staters_ of Cyzicus were a staple currency in the ancient world till they were superseded by those of Philip of Macedon. During the Peloponnesian War (431-404 B.C.) Cyzicus was subject to the Athenians and Lacedaemonians alternately, and at the peace of Antalcidas (387 B.C.), like the other Greek cities in Asia, it was made over to Persia. The history of the town in Hellenistic times is closely connected with that of the dynasts of Pergamum, with whose extinction it came into direct relations with Rome. Cyzicus was held for the Romans against Mithradates in 74 B.C. till the siege was raised by Lucullus: the loyalty of the city was rewarded by an extension of territory and other privileges. Still a nourishing centre in Imperial times, the place appears to have been ruined by a series of earthquakes--the last in A.D. 1063--and the population was transferred to Artaki at least as early as the 13th century, when the peninsula was occupied by the Crusaders. The site is now known as Bal-Kiz ([Greek: Palaia Kuzikos]?) and entirely uninhabited, though under cultivation. The principal extant ruins are:--the walls, which are traceable for nearly their whole extent, a picturesque amphitheatre intersected by a stream, and the substructures of the temple of Hadrian. Of this magnificent building, sometimes ranked among the seven wonders of the ancient world, thirty-one immense columns still stood erect in 1444. These have since been carried away piecemeal for building purposes by the Turks.

See J. Marquardt, _Cyzicus_ (Berlin, 1830); G. Perrot, _Exploration de
la Galatie_ (Paris, 1862); F. W. Hasluck and A. E. Henderson in
_Journal of Hellenic Studies_ (1904), 135-143. (F. W. Ha.)

CZARNIECKI, STEPHEN (1590-1665), Polish general, learnt the science of war under Stanislaw Koniecpolski in the Prussian campaigns against Gustavus Adolphus (1626-1629), and under Wladislaus IV. in the Muscovite campaign of 1633. On the 15th of April 1648 he was one of the many noble Polish prisoners who fell into the hands of Chmielnicki at the battle of "Yellow Waters," and was sent in chains to the Crimea, whence he was ransomed in 1649. He took an active part in all the subsequent wars with the Cossacks and received more disfiguring wounds than any other commander. When Charles X. of Sweden invaded Poland in 1655, Czarniecki distinguished himself by his heroic defence of Cracow, which he only surrendered under the most honourable conditions. His energy and ability as a leader of guerillas hampered Charles X. at every step, and though frequently worsted he from time to time inflicted serious defeats upon the Swedes, notably at Jaroslaw and at Kozienice in 1656. Under his direction the popular rising against the invader ultimately proved triumphant. It was he who brought King John Casimir back from exile and enabled him to regain his lost kingdom. It was against his advice that the great battle of Warsaw was fought, and his subsequent strategy neutralized the ill effects of that national disaster. On the retirement of the Swedes from Cracow and Warsaw, and the conclusion of the treaty of Copenhagen with the Danes, he commanded the army corps sent to drive the troops of Charles X. out of Jutland and greatly contributed to the ultimate success of the Allies. On the conclusion of the Peace of Oliva, which adjusted the long outstanding differences between Poland and Sweden, Czarniecki was transferred to the eastern frontier where the war with Muscovy was still raging. In the campaign of 1660 he won the victories of Polonka and Lachowicza and penetrated to the heart of the enemy's country. The diet of 1661 publicly thanked him for his services; the king heaped honours and riches upon him, and in 1665 he was appointed acting commander-in-chief of Poland, but died a few days after receiving this supreme distinction. By his wife Sophia Kobierzycka he left two daughters. Czarniecki is rightly regarded as one of the most famous of heroic Poland's great captains, and to him belongs the chief merit of extricating her from the difficulties which threatened to overwhelm her during the disastrous reign of John Casimir. Czarniecki raised partisan-warfare to the dignity of a science, and by his ubiquity and tenacity demoralized and exhausted the regular armies to which he was generally opposed.

See Ludwik Jenike, _Stephen Czarniecki_ (Pol.) (Warsaw, 1891); Michal
Dymitr Krajewski, _History of Stephen Czarniecki_ (Pol.), (Cracow,
1859).

CZARTORYSKI, ADAM GEORGE, PRINCE (1770-1861), Polish statesman, was the son of Prince Adam Casimir Czartoryski and Isabella Fleming. After a careful education at home by eminent specialists, mostly Frenchmen,[1] he first went abroad in 1786. At Gotha he heard Goethe read his _Iphigenie auf Tauris_, and made the acquaintance of the dignified Herder and "fat little Wieland." In 1789 he visited England with his mother, and was present at the trial of Warren Hastings. On a second visit in 1793 he made many acquaintances among the English aristocracy and studied the English constitution. In the interval between these visits he fought for his country during the war of the second partition, and would subsequently have served under Kosciuszko also had he not been arrested on his way to Poland at Brussels by the Austrian government. After the third partition the estates of the Czartoryskis were confiscated, and in May 1795 Adam and his younger brother Constantine were summoned to St Petersburg; later in the year they were commanded to enter the Russian service, Adam becoming an officer in the horse, and Constantine in the foot guards. Catherine was so favourably impressed by the youths that she restored them part of their estates, and in the beginning of 1796 made them gentlemen in waiting. Adam had already met the grand duke Alexander at a ball at the princess Golitsuin's, and the youths at once conceived a strong "intellectual friendship" for each other. On the accession of the emperor Paul, Czartoryski was appointed adjutant to Alexander, now Cesarevich, and was permitted to revisit his Polish estates for three months. At this time the tone of the Russian court was extremely liberal, humanitarian enthusiasts like Peter Volkonsky and Nikolai Novosiltsov possessing great influence.

Throughout the reign of Paul, Czartoryski was in high favour and on terms of the closest intimacy with the emperor, who in December 1798 appointed him ambassador to the court of Sardinia. On reaching Italy Czartoryski found that the monarch to whom he was accredited was a king without a kingdom, so that the outcome of his first diplomatic mission was a pleasant tour through Italy to Naples, the acquisition of the Italian language, and a careful exploration of the antiquities of Rome. In the spring of 1801 the new emperor Alexander summoned his friend back to St Petersburg. Czartoryski found the tsar still suffering from remorse at his father's assassination, and incapable of doing anything but talk religion and politics to a small circle of private friends. To all remonstrances he only replied "There's plenty of time." The senate did most of the current business; Peter Vasilevich Zavadovsky, a pupil of the Jesuits, was minister of education. Alexander appointed Czartoryski curator of the academy of Vilna (April 3, 1803) that he might give full play to his advanced ideas. He was unable, however, to give much attention to education, for from the beginning of 1804, as adjunct of foreign affairs, he had the practical control of Russian diplomacy. His first act was to protest energetically against the murder of the due d'Enghien (March 20, 1804), and insist on an immediate rupture with France. On the 7th of June the French minister Hedouville quitted St Petersburg; and on the 11th of August a note dictated by Czartoryski to Alexander was sent to the Russian minister in London, urging the formation of an anti-French coalition. It was Czartoryski also who framed the Convention of the 6th of November 1804, whereby Russia agreed to put 115,000 and Austria 235,000 men in the field against Napoleon. Finally, on the 11th of April 1805 he signed an offensive-defensive alliance with England. But his most striking ministerial act was a memorial written in 1805, but otherwise undated, which aimed at transforming the whole map of Europe. In brief it amounted to this. Austria and Prussia were to divide Germany between them. Russia was to acquire the Dardanelles, the Sea of Marmora, the Bosphorus with Constantinople, and Corfu. Austria was to have Bosnia, Wallachia and Ragusa. Montenegro, enlarged by Mostar and the Ionian Islands, was to form a separate state. England and Russia together were to maintain the equilibrium of the world. In return for their acquisitions in Germany, Austria and Prussia were to consent to the erection of an autonomous Polish state extending from Danzig to the sources of the Vistula, under the protection of Russia. Fantastic as it was in some particulars, this project was partly realized[2] in more recent times, and it presented the best guarantee for the independent existence of Poland which had never been able to govern itself. But in the meantime Austria had come to an understanding with England as to subsidies, and war had begun.

In 1805 Czartoryski accompanied Alexander both to Berlin and Olmutz as chief minister. He regarded the Berlin visit as a blunder, chiefly owing to his profound distrust of Prussia; but Alexander ignored his representations, and in February 1807 he lost favour and was superseded by Andrei Eberhard Budberg. But though no longer a minister Czartoryski continued to enjoy Alexander's confidence in private, and in 1810 the emperor candidly admitted to Czartoryski that his policy in 1805 had been erroneous and he had not made a proper use of his opportunities. The same year Czartoryski quitted St Petersburg for ever; but the personal relations between him and Alexander were never better. The friends met again at Kalisch shortly before the signature of the Russo-Prussian alliance of the 20th of February 1813, and Czartoryski was in the emperor's suite at Paris in 1814, and rendered his sovereign material services at the congress of Vienna.

On the erection of the congressional kingdom of Poland every one thought that Czartoryski, who more than any other man had prepared the way for it, would be its first governor-general, but he was content with the title of senator-palatine and a share in the administration. In 1817 the prince married Anna Sapiezanko, the wedding leading to a duel with his rival Pac. On the death of his father in 1823 he retired to his ancestral castle at Pulawy; but the Revolution of 1830 brought him back to public life. As president of the provisional government he summoned (Dec. 18th, 1830) the Diet of 1831, and after the termination of Chlopicki's dictatorship was elected chief of the supreme council by 121 out of 138 votes (January 30th). On the 16th of September his disapproval of the popular excesses at Warsaw caused him to quit the government after sacrificing half his fortune to the national cause; but it must be admitted that throughout the insurrection he did not act up to his great reputation. Yet the energy of the sexagenarian statesman was wonderful. On the 23rd of August he joined Girolano Ramorino's army-corps as a volunteer, and subsequently formed a confederation of the three southern provinces of Kalisch, Sandomir and Cracow. At the end of the war he emigrated to France, where he resided during the last thirty years of his life. He died at his country residence at Montfermeil, near Meaux, on the 15th of July 1861. He left two sons, Witold (1824-1865), and Wladyslaus (1828-1894), and a daughter Isabella, who married Jan Dzialynski in 1857. The principal works of Czartoryski are _Essai sur la diplomatie_ (Marseilles, 1830); _Life of J. U. Niemcewiez_ (Pol). (Paris, 1860); _Alexander I. et Czartoryski: correspondance ... et conversations_ (1801-1823) (Paris, 1865); _Memoires et correspondance avec Alex. I._, with preface by C. de Mazade, 2 vols. (Paris, 1887); an English translation _Memoirs of Czartoryski, &c._, edited by A. Gielguch, with documents relating to his negotiations with Pitt, and conversations with Palmerston in 1832 (2 vols., London, 1888).

See Bronislaw Zaleski, _Life of Adam Czartoryski_ (Pol.) (Paris,
1881); Lubomir Gadon, _Prince Adam Czartoryski_ (Pol.) (Cracow, 1892);
Ludovik Debicki, _Pulawy_, vol. iv.; Lubomir Gadon, _Prince Adam
Czartoryski during the Insurrection of November_ (Pol.) (Cracow,
1900). (R. N. B.)

FOOTNOTES: