Chapter XVIII: Part II: Marine Invertebrates (13)

This is a prominent genus of the /Veneridae/. Its chief feature is the total want of lateral teeth. There are several large species in California.

^T. staminea, T. laciniata.^ These are the most noticeable
species. The former is sold in the San Francisco markets as the
"hard-shell clam." The shell of this species is from two to three
inches in length and of somewhat less height, rounded, and heavy.
The sculpturing consists of radiating ribs traversed by strongly
marked growth-lines. The teeth are strong, and the pallial sinus
is deep. /T. laciniata/ is much like the last, but its surface is
reticulated by a crisscross design that is very striking. It also
has a deep pallial sinus. These two species are of Southern range.
They burrow in gravelly places, among stones, between tide-marks,
and their presence may frequently be detected when walking along
the beach at low tide by seeing a sudden jet of water ejected from
a little hole in the mud or gravel. The animal, becoming alarmed at
the approach of something, suddenly snaps shut its valves, and thus
forces out some water through its siphons. The foot is very strong
and often byssiferous in this genus. (Plate LXXXIII.) [pg452]

GENUS ^Saxidomus^

^S. nuttallii.^ The last of the larger west-coast /Veneridae/ which
we shall examine. The genus is very closely allied to /Tapes/, and
no doubt might better be considered as its subgenus. The shell is
brownish-white, three to four inches in length, and heavy, rough,
and coarse-looking, with irregular concentric ridges. There is
no lunule, but a large external ligament is very prominent just
back of the beaks. Within it is white, with a deep pallial sinus.
Just below the ligament area is a zone of translucent, agate-like
shell-structure. This large clam, with several others of the same
genus, lives in shallow water near shore.

FAMILY ~PETRICOLIDAE~

GENUS ^Petricola^

^P. pholadiformis.^ Along the Jersey coast, especially about
Atlantic City, there are small patches of clay or hard tenacious
mud which lie just at the edge of the sea. As the beating of
the surf gradually encroaches upon these hard fragments of once
extensive clay-beds, many specimens of this curious bivalve mollusk
are washed out from their burrows in this clay and cast upon the
sandy beach. The animal has long siphons which are united about
one third of the way to their ends. Although this creature is
allied to the /Veneridae/, the degree of mantle fusion present is
much greater, leaving in this case only a fairly long slit through
which the foot may protrude. The shell is very dissimilar to that
of any of the /Veneridae/, and in many respects, judging from a
conventional standard, is a remarkable form. It is exceedingly
thin, is of a chalky texture, gapes widely posteriorly, and is
ornamented with transverse ribs, which are feeble upon the long
produced posterior portion of the shell, but strong in the anterior
part, where they are crossed by the coarse lines of growth, which
appear like vaulted scales upon the ribs. The color is a dull
white. There are two cardinals in each valve and no laterals.
Length one and a quarter to two and a half inches; height one half
to three quarters of an inch. This species passes its entire life
in the burrow it has made for itself in the clay. Its only motions
are made in climbing to the entrance of its burrow or in retreating
far out of sight within its depths. Its siphons are tipped with a
dark or drab color as a measure of protection from the predaceous
crabs which range about the mud surfaces near tidal marks, and are
always upon the lookout for succulent bits of flesh.

^P. carditoides.^ A petricola of the Californian coast, very
similar in its habits to the east-coast form. It bores, however,
not only into clay, but also into soft rocks in order to effect a
permanent lodgment. Often this species occupies a hole which it has
discovered already existing; in this case its shell grows to fit
the surroundings. The hinge-teeth, and sculpturing are frequently
reduced and sometimes are quite obsolete; but the shell has the
chalky, thin texture that is characteristic of the genus. [pg453]

There is another family of rock- and mud-boring bivalves which
superficially resemble the petricolas, but their anatomical
organization removes them to a little distance from the
/Petricolidae/. They are considered further on, under the name of
/Pholadidae/.

FAMILY ~CARDIIDAE~

GENUS ^Cardium^

This is another important family of the /Pelecypoda/, which, with the /Veneridae/, the /Mactridae/, and the /Tellinidae/, is entitled to distinction on account of its high organization, its high type of shell, its universal geographical distribution, and its great beauty. The dominant genus is /Cardium/--a name given on account of the fact that the shell is shaped like a heart. The animal has a very long, recurved, and surprisingly strong foot. The mantle-edges are quite freely open to the siphonal region and are highly papillate and waved. The siphons are usually very short, but have wide exterior openings and are also strongly papillate about their margins. The gills are obliquely situated, and seem to be thicker and heavier than is usual in pelecypods; they are much folded, the outer lamella being the smaller. With such a pointed foot and such short siphons /Cardium/ is obviously not a deep-burrowing genus; but it does partially bury itself in soft semi-liquid sand. Its progression is effected by leaps which it is enabled to make by reaching far out with its foot, then suddenly twisting to one side and throwing the shell several inches. The shell is ventricose, is closed or gapes slightly posteriorly, and has prominent subcentral umbones and an external ligament. The sculpture-scheme of /Cardium/ (if the shell is not perfectly smooth) is one of radiating ribs or ridges, which, being regular, form a perfect crenulation of the ventral margin. There are two cardinal teeth in the center, and one lateral tooth upon both the anterior and the posterior side: the latter are situated at some little distance from the beaks.

^C. magnum.^ The largest and finest "cockle" of the east coast of
the United States. It is, indeed, one of the finest cockles in the
world. The almost perfect heart-shape is striking. The posterior
side is somewhat flatly depressed. The thirty-three to thirty-seven
regularly disposed, broad, radiating ribs; the regularly crenulated
margins; the yellowish-brown color garnished with transverse rows
of chestnut or [pg454] purple lines or spots; the brownish-purple
posterior area--all combine to make this large /Cardium/ a
beautiful species. Its length is four inches; height five and a
quarter inches. It is a very abundant species on the open Florida
beaches, where it is often left exposed and alive at very low
tides. (Plate LXXXIV.)

^C. isocardia.^ This also is a Floridian species, of elongated
heart-shape and with radiating ribs. It is not more than half
as large as the last-described species. The ribs are decorated
with erect vaulting scales which are exaggerated portions
of growth-lines. The beaks are smaller in proportion than
in /C. magnum/. The shell is brown to straw-color, stained
with purplish-brown without, and has a bright salmon-red or
purplish-pink interior. The margins are deeply crenulated. The
teeth are arranged as in the last-described species. It is very
common on the beaches of western Florida. (Plate LXXXIV.)

^C. serratum^, ^C. laevigatum^. These two species have a perfectly
smooth surface, and inflated, globose, heart-shaped shells, and
are of a creamy-white color, suffused with a yellowish, golden
tint which suggests the color of butter. Some forms are shiny, and
citron-yellow and pinkish toward the margins, whence the name of
"peach-shell." Height one to two inches. Not uncommon upon Florida
beaches. (Plate LXXXIV.)

^C. mortoni.^ Another of the smooth forms of /Cardium/ (placed in
the subgenus /Laevicardium/). It occurs in Florida and also extends
up the coast to Cape Cod, being very abundant in Long Island Sound.
In the neighborhood of Martha's Vineyard and along the north shore
of Long Island this very pretty little species has been reported as
occurring in soft ground even above low-tide mark, near the mouths
of creeks. It is enough to say of it that it is a smaller edition
of /C. laevigatum/ and may be further distinguished by a purple
blotch on the posterior margin, just within the valves, the general
color within being bright yellow. In young specimens, zigzag lines
of dark fawn-color upon the pale-yellowish background of the smooth
exterior surface of the shells are a noticeable feature. The
largest specimens measure an inch in length and nearly the same in
height. The long cirri upon the siphons are striking.

^C. substriatum.^ A cockle of this inflated, smooth type, which
strongly resembles the east-coast form, found upon the Pacific
coast. The name indicates that it is not altogether smooth, a
fact only revealed, however, by a magnifying-glass. It is about
one half of an inch in length, and of a light drab-color, spotted
and sometimes radially lined with yellowish-brown. Professor Keep
likens this species in both shape and color to a sparrow's egg.
(Plate LXXXIV.)

^C. elatum.^ A veritable giant among the cardiums. It is found on
the southern Californian coast, though rarely north of the Mexican
border. It is of the smooth, glossy type belonging to the subgenus
/Laevicardium/. It attains a diameter of six inches, and is of a
creamy-yellow appearance.

^C. corbis^, ^C. quadrigenarium^. These two Californian cockles
are of the ribbed type displayed in the eastern /C. magnum/ and
/C. isocardia/. /C. corbis/ is found in the northern Californian
and Puget Sound region, [pg455] and /C. quadrigenarium/ on
the southern shores of California. The former is a full, round,
heart-shaped shell with about thirty somewhat scaly ribs. The edge
of the shell is deeply toothed; the color light brownish; the
diameter from two to three inches. It preserves all the features
of the genus as regards both shell and anatomical characters. The
other species, /C. quadrigenarium/, very strongly resembles /C.
magnum/ in size and shape. It lacks the flattened area on the
posterior portion of the shell which is characteristic of the
east-coast species, and its uniform brownish-white coloration is
less striking. It has about forty regularly spaced, radiating ribs,
which are smooth upon the umbonal region, but elsewhere are armed
with spiny processes. Diameter about six inches. (Plate LXXXIV.)

^C. islandicum^, ^C. pinnulatum^. Both of these are cold-water
species and occur along the New England coast. The former has
a shell which varies from one half of an inch to two inches in
length, and has from thirty-six to thirty-eight sharp, three-sided,
radiating ribs, the furrows between them being rounded and wrinkled
by growth-lines. A yellowish-brown epidermis covers the shell and
bristles into a sort of fringe upon the sharp edges of the ribs.
/C. islandicum/ cannot be said to be a very common species in New
England, although collectors have so reported it. Specimens from
Massachusetts are not as large as those of more northern habitat.
It does not occur south of Cape Cod. /C. pinnulatum/ is one of the
"small fry" among the cockles. Its largest diameter is less than
one half of an inch; but what it lacks in size it seems to endeavor
to make up in abundance, for it is scattered everywhere along the
coast from New York northward. Specimens can nearly always be found
in the stomachs of fishes, which, by the way, form an excellent
hunting-ground for rare species of mollusks of small size. There
are twenty-six slightly rounded ribs, with deep linear grooves
between them. Upon the ribs, especially in the posterior portion
of the shell, are arched scales, folded so as to appear like blunt
spines. The species may easily be distinguished from the young of
/C. islandicum/ by the smaller number of ribs. The animal, /C.
pinnulatum/, is said to be exceedingly lively and able to make
rapid progress over gravelly bottom by executing sudden leaps.
It has a long, recurved, very strong foot, and its movements are
effected as described above. It is abundant at Bar Harbor. [pg456]

FAMILY ~MYIDAE~

GENUS ^Mya^

In this family we encounter, rather suddenly, some new features not heretofore seen in the pelecypod structure. In the first place, the siphons are enormously large, are united, and are surrounded by a leathery epidermis. The mantle-edges are fused together along the entire ventral margin, except for a small slit through which the foot may project. Although the animal may withdraw the long siphons into its shell, yet they remain to a certain extent exposed, for the valves gape widely posteriorly, and only slightly less so anteriorly. In the economy of these forms the shell seems to play a less important part than it does in the /Veneridae/, in the /Tellinidae/, and generally in those families whose shells are strong and, closing firmly, afford the animal within a real protection. The shell of /Mya/ (the principal genus) is thin, white, and of a softer chalky texture; it gapes widely "fore and aft," and has a loosely constructed hinge apparatus, consisting of an erect projecting tooth, which fits into a pit in the opposite valve.

^M. arenaria.^ This is the common "soft-shell clam" of New England.
Its range is from Cape Cod to Greenland and Great Britain. Upon
the Maine coast it is very extensively gathered and sold to the
Banks fishermen for bait. Its use as food for man is probably not
very great, yet it is always to be seen on sale in the markets of
New England coast towns. It cannot compare in flavor with /Venus
mercenaria/, the "hard-shell clam" south of Cape Cod. /M. arenaria/
lives between tides in muddy, sandy, pebbly, or even rocky ground,
where it can find material in which it can burrow and hide itself.
It lies just below the surface, with its siphons projected into
the water. When the water recedes, /Mya/ draws in its siphons
and awaits the return of the tide, every now and then [pg457]
ejecting a jet of water into the air. The shells vary considerably
in size and thickness of valves. Large specimens are three and a
half inches long and two inches high. Our forefathers were not
always well posted upon the habits of mollusks, even though they
may have relished them in chowders and believed their flesh to
possess valuable curative properties. John Winthrop, in 1634, gave
a list of useful American animals, in which he remarked: "Clam,
white; their broth is most excellent in all intermitting fevers,
consumption, etc. These clams feed only on sand." What marvelous
digestive powers!

FAMILY ~SOLENIDAE~

In this family are included the long, slender bivalves commonly known as "razor-shells." Every one who has been to the sea-shore has become familiar with these odd-looking mollusks, for their valves are always to be found upon every beach. Their station is upon sandy flats or bars more or less exposed at low tide. They burrow into the sand perpendicularly to a depth of two or three feet, remaining hidden most of the time. Occasionally a colony of them will be seen, each one projecting slightly from his burrow. If approached most cautiously some of them may be captured, but if the sand is jarred they all take fright and disappear in an instant. It is no easy matter to capture a "razor" when once he has taken warning, for he will dig down into the sand about as fast as one can follow with a spade. A good way to catch one is to approach his burrow carefully, and then plunge a spade obliquely down below him, thereby [pg458] cutting off his retreat. So tenaciously will they cling to the sand by expanding the muscular foot that the shell may be pulled entirely off the body before they will let go.

GENUS ^Ensis^

^E. directus^ (^Solen ensis^, ^Ensis americanus^). The common
species upon the New England and Jersey coasts. The foot is long,
and protrudes from one end of the long shell; it is also very
strong, and capable of change at will into almost any form, from a
pointed bulb to a flat disk. The siphons, which project from the
opposite end of the shell, are short and are not united. The gills
are long. The juxtaposition of these organs is at first confusing,
because the greatly elongated form of the shell and the habits of
the animal in burrowing vertically into the sand have caused the
foot to be pushed farther away from the posterior portion of the
shell and to protrude in a direction just opposite to the siphons.
The shells are bent or slightly curved; they gape at both ends; and
they are fitted with very small interlocking teeth at the upper
corner of the posterior end. The color is white, but a yellowish or
greenish glossy epidermis covers the entire test. Length about six
inches. The manner in which the animal makes its rapid descent into
the sand is very interesting. First extending the foot lengthwise
into a point, it plunges it into the sand; then, by forcing water
into the organ it expands it, thus pushing away the sand on all
sides; and still further expanding the foot at the end into a disk,
it secures an anchorage which enables it to draw down its shell. By
quick repetition of this process /Ensis/ can get out of sight in a
remarkably sudden manner.

GENUS ^Solen^

^S. viridis.^ A smaller species, about two inches in length, and
with a nearly straight light-green shell. It is often abundant from
New Jersey southward.

^S. sicarius.^ The common Californian species of Northern range. It
is only about two inches long, and is rounded anteriorly, but is
chopped off squarely behind. It is slightly curved and white, and
has a glossy brown epidermis.

^S. rosaceus.^ Another species of Southern range, very similar
in form to the last, but straighter and rosy-white in color. The
epidermis is glossy brown. Length two inches. [pg459]

GENUS ^Tagelus^

^T. gibbus.^ The extended range and shore station of this
exceedingly abundant species will cause it to be among the first
accessions to the cabinet of the collector south of Cape Cod. It
burrows deep in sand and mud, leaving two small openings to the
hole for the accommodation of its two excessively long siphons.
As in /Solen/ and /Ensis/, the foot is large and muscular,
tongue-shaped, and capable of remarkable change of form and great
freedom of movement. The long white siphons, separated from the
base and each provided with orange-colored eyes (or, rather, a
rudimentary sort of visual organs), are the most important feature.
The apex of the hinge is not, as in /Solen/ and /Ensis/, at the
end of the shell, but is more conventionally placed near the
middle; the cardinal teeth are very small, two upon each valve
and interlocking; a flat, oblong, callous process serves as a
fossette. The dorsal and ventral margins are parallel, and gape
at both ends; the shell is white, and is covered with a dense
yellowish epidermis, which, passing the ventral margin, appears to
become continuous with the thickened mantle-edge. There is no other
species north of Hatteras with which this could be confounded.
The double entrance to the burrow, which may be discovered about
low-tide mark, is unique. /T. gibbus/ is a good species to examine
for the crystalline stylet in the digestive tract.

FAMILY ~GLYCIMERIDAE~

GENUS ^Glycimeris^

^G. generosa.^ A large shell of the Pacific coast, occurring
most abundantly in Puget Sound waters, where it frequents muddy
shallows. It is a remarkable pelecypod in respect to its siphons
and the degree of mantle fusion. The appearance of the animal
is that of a huge pair of [pg460] united siphons, protected
laterally at their larger end by two white, widely gaping valves.
The very small pedal opening in the line or mantle juncture
indicates a very small foot. (Plate LXXXIV.)

FAMILY ~PHOLADIDAE~

There is a striking resemblance between the shells of this rock-boring family and those of the petricolas--a resemblance which consists principally in the texture of the shell and the tendency to different types of sculpturing upon the posterior and anterior surfaces of the valves.

GENUS ^Pholas^

In /Pholas/ the anterior part of the hinge-margin is reflected back over the umbones, and a long rib-like tooth springs from under the umbonal region and curves out almost to the center of the valves. The shell gapes "fore and aft," and is thin, white, very hard, and brittle. The animal has a short, truncated foot and a small orifice in the mantle through which the foot may be projected. The siphons are long and are united almost to their ends. Dorsally, an exposed portion of the animal is protected by accessory calcareous plates. The habits of /Pholas/ are very interesting. It is found in holes gouged out of solid rock or out of pieces of wood; sometimes, like /Petricola/, it may be found excavating in hard clay. As the anterior end of a /Pholas/ shell is the larger in diameter, and is the end which is most deeply buried in the rock (the opening of the burrow being comparatively small), there was some mystery as to the way in which the creature manages to get inside its rocky dwelling. Observations in aquaria have shown that the young /Pholas/ begins his process of home-building very early in life. The wearing away of the stone is effected by constantly turning the shell around, scraping with the anterior edges of the valves. A lodging-place having been secured, /Pholas/ is obliged to work constantly to enlarge his burrow for the accommodation of his growing shell. The long siphons may project from the hole and draw in food and breath, but the animal is a prisoner for life. When /Pholas/ has withdrawn his long siphons he is reasonably secure from his enemies, but [pg461] nevertheless thousands of them are destroyed by predatory starfishes, who know how to get at their victims. The restless crustaceans, ever on the outlook for a meal, often nip the siphons of the rock-dwellers, and a kind of worm sometimes attacks them, and, destroying the animal, proceeds to occupy the empty shell and burrow.

^P. costata.^ This species has a wide geographical range, being
found from Cape Cod to South America, but it is not abundant north
of Hatteras. In Florida it burrows deep in sand as well as in wood
or rock. On account of its white color and suggestive shape and
sculpture, it has received the popular name of "angel's-wings." It
grows to a length of seven or eight inches.

^P. truncata.^ This has much the same range as the last, but is
more commonly to be found in New England waters. It also burrows
in any hard substance, or in mud above low-water mark. It is
especially common in peat-banks.

^P. californica.^ A Californian /Pholas/. The shell is about three
inches in length, and resembles in all features and habits the
/Pholas/ of the east coast. Differences in the shell indicate that
it is a distinct species.

GENUS ^Zirphaea^

^Z. crispata.^ A species of Northern range, occurring but sparingly
in New England, in hard clay or rocky burrows. It may be identified
at once by the furrow which passes from the beaks across the valves
to the lower edges of the shell and divides the surface of the
valve into two areas. The anterior area is decorated with radiating
toothed ribs; the posterior area is smooth. This conchological
feature of the genus is very [pg462] curious; it may be observed
also in several deep-sea genera and in certain extinct fossil
forms. The length of this shell is about two inches. This species
also occurs in California, where its favorite station is in hard
tenacious clay. Length two to four inches.

FAMILY ~TEREDINIDAE~

GENUS ^Teredo^

^T. navalis.^ This species is worm-like in form, but it has a small
bivalve shell at the larger end, and near the anterior extremity
two calcareous appendages called pallets, beyond which extend two
siphons. Along the surface of the mantle is secreted a continuous
shelly tube which lines the burrow. This mollusk, commonly called
the "ship-worm," is exceedingly destructive, perforating with its
burrows submerged timber and soon rendering it useless. Various
means are taken to protect ships, the piles of wharves, buoys, and
the like, against its ravages; copper sheathing, large-headed nails
driven close together into the wood, verdigris paint, and so on,
being used with more or less effect. Vast numbers of these animals
enter the wood and burrow in various directions, but they never
interfere with one another, a thin partition of wood always being
left between adjacent burrows. How they effect the burrowing is
not determined, but it is supposed to be by means of the pallets.
/Teredo/ does not, like the boring isopod /Limnoria lignorum/, feed
upon the wood. Its food consists of microscopic organisms which
are taken in through the incurrent siphon. In temperate waters /T.
navalis/ grows sometimes to the length of six inches; in tropical
waters it attains the length of two feet.

There are three other species of /Teredo/ and one of the genus
/Xylotrya/ on our Northern shores; /T. navalis/ is, however, the
most common and most destructive. In Southern waters there are many
other forms of these boring mollusks. [pg463]

FAMILY ~PANDORIDAE~

GENUS ^Pandora^

^P. trilineata.^ A little New England shell, remarkable on account
of its extreme flatness. When looking at this shell before opening
it, one naturally wonders where the animal finds room to exist
between two such disk-like valves. The animal is very thin, with
largely united mantle-edges, widely separated feeble adductor
muscles, and a fairly large tongue-shaped foot. The shell is
nacreous, rounded anteriorly, and produced posteriorly into a sort
of upturned tip which gapes to accommodate two little siphons. The
dorsal hinge-margin is excavated and curved. Length about one inch.
It is abundant at Cape Cod, in sandy stations, on oyster-beds, and
is found from Maine to Florida. [pg464]

TABLE SHOWING THE CLASSIFICATION OF THE CEPHALOPODS DESCRIBED IN THIS CHAPTER

CLASS =CEPHALOPODA=

Orders Genera Species

Subclass =Tetrabranchiata=

^Nautilus^

Subclass =Dibranchiata=

~OCTOPODA~ ^Octopus^
^Argonauta^ ^A. argo^

~DECAPODA~ ^Spirula^
^Ommastrephes^ ^O. illecebrosus^
^Sepia^
^Loligo^ ^L. Pealei^
^L. brevis^

CLASS =CEPHALOPODA=

The /Cephalopoda/ form a singularly isolated group, and are so superior in organization and intelligence to all other mollusks that it is difficult to believe that they are first cousins to the lethargic gasteropod and the simply constructed bivalve. But the class bears the stamp of its origin in a mantle, a radula, and a disposition of internal organs and functions which, although highly perfected, is essentially molluscan.

Along the Atlantic coast of the United States, particularly in its northern portion, occur several examples of cephalopods belonging to the genera /Ommastrephes/ and /Loligo/, all the species of which are referred to, in common parlance, as "squids." They frequent shallow water, and are often to be found in weirs, darting about with rapid, spasmodic movements, or perhaps lying motionless on the bottom. The squids enter the weirs for the purpose of capturing the young mackerel which are caught in these traps. The squid lies quietly upon the bottom, which it simulates so closely in color as to be almost invisible, and when [pg465] a school of fishes swims over it, darts suddenly into the midst of it, seizes a fish with its sucker-bearing arms, and kills it by the bite of its parrot-like beak or jaws. Sometimes it happens that squids, while pursuing fish too near shore, precipitate themselves upon the beach, where they flounder about, ejecting water from their siphons, which pushes them only farther away from the water, and squirting out "ink" from their ink-sacs in a vain endeavor to hide themselves from view. On bright moonlight nights squids often go ashore in vast numbers, and perish within a few inches of their native element, which they seem to be unable to regain. These creatures usually swim backward, and the theory is that, dazzled by the bright light of the moon, they continue to gaze at it while swimming, and if there happens to be a shore in the direction of their movements, they suddenly find themselves beached. The fishermen of Canada and New England take advantage of this habit and capture great quantities of squids by placing bright lights in the bows of their boats and then rowing toward shore, thus driving the squids out of the water. The Banks fishermen use them as bait for catching cod. The right claimed by American fishing-schooners to purchase squids in Newfoundland has helped to keep alive the quarrel between Canadian and American fishermen, which has vexed their respective governments for many years.

The range in size among the species of this class is very remarkable. The little sepiolas are about an inch long; the squids of our coasts vary in length from eight inches to one foot; and the giant /Architeuthis/ of the North Atlantic measures, often, fifty feet from the end of its arms to the tip of its tail. Such a creature, with its long arms provided with suckers, its powerful jaws, and its rapid, alert movements, is a formidable foe. These animals have been the basis of many legends about sea-serpents and sea-monsters. A gruesome story of an octopus is told by Victor Hugo in "The Toilers of the Sea," where he gives a thrilling account of a man's encounter with a devil-fish in a cave. One who has read this tale has a vivid picture in his mind of the giant squid, and the danger of meeting one of these many-armed foes. Victor Hugo's devil-fish, [pg466] however, is an animal not true to nature, but a composite, having the attributes of the polyp and of the octopus, and the name of a large ray of Southern waters, a real fish, the /Cephaloptera/, known in its localities as devil-fish. This monstrosity of the novelist's imagination has, however, done more to acquaint the general public with these interesting cephalopods than have the descriptions of scientists.

The giant squid, which is such a dangerous foe, has its own enemy in the sperm-whale. The cachalot swims through the water with its lower jaw hanging, the cephalopod grasps the jaw, and the whale then shuts his capacious mouth upon it. Whalemen describe conflicts between these enormous creatures, the whale always being the conqueror. Sperm-whales killed by man often eject great quantities of the squids in their death throes, showing this food to be almost their exclusive diet.

The name "cephalopod," meaning "feet around the head," is descriptive in part of their anatomy. The head is usually marked off by a neck-constriction, and it bears two highly organized eyes. The foot is fused in part with the head above the eyes and around the mouth; on the upper side it is divided into eight or ten long arm-like processes, bearing suckers, which act as organs of prehension. The under part of the foot forms a tube called the funnel. Through the funnel the animal expels water from the mantle cavity, and thus propels itself through the water.

The mantle covers the body of the animal, and is a cup-shaped or conical envelope, open only at the anterior end, through which project the head and siphon or funnel. It is attached to the body by a line on the dorsal side, the anterior margin being free and open, but provided with an arrangement of cartilages by which it can be hooked on to the siphon, thus completely closing the entrance to the mantle cavity. The mantle is very muscular, and is constantly expanding and contracting, taking water into the mantle cavity through the mantle opening for respiratory purposes, or expelling it through the siphon for propulsion; in the latter case the mantle opening is closed at the moment of ejecting the water. When the siphon is in its normal position [pg467] the animal swims backward; but it can be turned back over the edge of the mantle, giving a forward movement.

The surface of the mantle is covered with pigment-cells (/chromatophores/). There are sets of chromatophores containing different colors. The cells are opened or closed at will by muscular action of their walls. When open the cells seem to fuse together, giving a solid color-surface, or spots of color as desired, in blue, red, yellow, or brown; when closed they seem as specks on the almost transparent tissues of the animal. Flashes of changing color follow one another with great rapidity over the living animal. In swimming it assumes the color of its surroundings.

Another curious means of protection possessed by the dibranchiate cephalopods is an ink-bag, the brown or black secretions of which are ejected through the siphon, clouding the water when the animal wishes to escape from danger. The ink taken from the ink-sac of /Sepia/ is an article of commerce.

Only /Nautilus/ and the female /Argonauta/ have the characteristic external shell of mollusks. In all other forms the shell is internal or is invested in the integument of the mantle. Of such is the cuttlebone of commerce, which is a calcareous leaf-like body obtained from /Sepia/, the cuttlefish. The common squid /Loligo/ has a horny substance situated in the dorsal side of the mantle, called the pen. /Spirula/ has a spiral internal shell divided into chambers. Vast numbers of these shells are cast upon the beaches of the Pacific Islands, and they have also been found on the shore of Nantucket.

Cephalopods are separated into two subclasses. In the first, the /Tetrabranchiata/, there are four branchiae, four nephridia, and four auricles. They are without an ink-sac, and have the foot divided into lobes bearing sheathed tentacles. /Nautilus/ is the only genus.

SUBCLASS =TETRABRANCHIATA=

GENUS ^Nautilus^

Probably the best-known cephalopod is /Nautilus/--the pearly-shelled, chambered nautilus made immortal in the beautiful poem of Oliver Wendell Holmes. The shell of /Nautilus/ is a flat spiral; the interior is divided by septa forming a series of chambers; [pg468] the septa are perforated, and through the opening runs a tube or prolongation of the body, the siphuncle, which extends to the tip of the shell. The chambers are filled with gas. The animal in the course of its growth moves forward into a newly formed chamber and builds a new septum, closing the cavity last occupied. /Nautilus/ lives among the coral reefs of the southern Pacific. Its four or five species are the remnants of a once very extensive race of cephalopods. The fossil remains of many species of /Nautilus/, together with various other genera of shell-bearing cephalopods, indicate that this group has seen its best days. The dibranchiate genera, however, appear to have reached their maximum at the present day.

SUBCLASS =DIBRANCHIATA=

The second subclass, the /Dibranchiata/, is characterized by two branchiae and two auricles. The main part of the foot is divided into eight or ten long arms provided with numerous suckers arranged in from one to four rows on the ventral side of the arms. They have also an ink-sac. The /Dibranchiata/ are divided into two orders: the /Octopoda/, which have eight arms, and comprise the /Octopus/ and /Argonauta/; and the /Decapoda/, which have ten arms, and comprise /Spirula/, /Ommastrephes/, /Sepia/, and /Loligo/. In these animals two of the ten arms are longer than the others, and these tentacular arms have suckers only on their broadened, club-like ends, they are kept retracted within grooves, one on each side of the head, except when needed for prehension. [pg469]

GENUS ^Argonauta^

^A. argo.^ In this species, the paper-nautilus, the shell, which is
possessed only by the female, is not chambered. The animal rests in
the shell, but has no organic connection with it other than by the
membranous expansions at the extremities of the two dorsal arms,
which secrete it and hold it in place. The purpose of the shell is
to hold and protect the eggs.

GENUS ^Loligo^

^L. Pealei.^ In this species the body is cylindrical, tapers to a
point, and has a flat appendage in front. The fins are terminal,
half, or more than half, as long as the body, united in a point
posteriorly, and obtusely rounded on the outer angles. The head
is a little narrower than the mantle. There are eight sessile,
sub-triangular arms furnished with two series of suckers which
are hemispherical and stalked, and two long retractile tentacular
arms dilated at the extremities, bearing four rows of suckers. It
has a pen- or quill-shaped cartilaginous substance in the dorsal
integument of the mantle. Common from Cape Cod to South Carolina.

^L. brevis.^ A small short-bodied species, with short rounded
caudal fins. It is common from South Carolina to Florida, and
extends as far north as Delaware Bay.

GENUS ^Ommastrephes^

^O. illecebrosus.^ A species similar to /L. Pealei/, but with
shorter fins. These are broad and pear-shaped, one third wider than
they are long, and usually reach less than one half the length of
the mantle. They are straight on the posterior end, and form nearly
a right angle, while the upper margins are rounded. The head is
as broad as the mantle. The arms are stout and taper to an acute
point. The tentacular arms are long when expanded. The species
is abundant from Cape Cod to Newfoundland, and is found as far
south as Newport, Rhode Island. This is the squid which is used so
extensively in the Banks fishery as bait. It [pg470] visits the
shores in large schools, presumably in pursuit of prey, and often
itself becomes the victim. It is a beautiful creature from its
varying colors, which are truly wonderful. It changes in a moment
from vivid red to deep blue, purple, orange, and so on, the colors
often passing over it in flashes as it swims along. [pg471]

VIII

CHORDATA

TABLE SHOWING THE CLASSIFICATION OF THE CHORDATA DESCRIBED IN THIS CHAPTER

Phylum =CHORDATA=

Class =UROCHORDA= or =TUNICATA=

Order =LARVACEA= (/Free-swimming, pelagic; Tunicata having
caudal appendages/)

Genera Species

^Appendicularia^

Order =THALIACEA= (/Free-swimming Tunicata, without caudal
appendages; single or in colonies; muscles of body-wall
arranged in complete or in interrupted ring-like bands/)

Suborder =CYCLOMYARIA= (/Cask-shaped bodies with complete
rings of muscular bands; oral and atrial apertures at
opposite ends of the body/)

^Doliolum^

Suborder =HEMIMYARIA= (/Spindle-shaped bodies; muscular bands
in incomplete rings; oral and atrial apertures subterminal/)

^Salpa^

Suborder =PYROSOMATA= (/Hollow cylindrical colonies; zooeids
embedded in a gelatinous wall; oral apertures open on
the outer, atrial apertures open on the inner surface of
cylinder/)

^Pyrosoma^

Order =ASCIDIACEA= (/Mostly fixed Tunicata; single or in
colonies; tests of considerable thickness/)

Suborder =ASCIDIA SIMPLICES= (/Possess distinct tests;
usually permanently fixed/)

Genera Species

^Molgula^ ^M. manhattensis^
^M. pellucida^
^M. arenata^
^Cynthia^ ^C. pyriformis^
^C. partita^
^C. carnea^
^Boltenia^ ^B. clavata^
^Ascidia^ ^A. amphora^
^A. callosa^

Suborder =ASCIDIA COMPOSITAE= (/Fixed colonies; the zooeids
embedded in a common gelatinous material; without separate
tests/)

^Botryllus^ ^B. gouldii^
^Amar[oe]cium^ ^A. pellucidum^

[pg474]

CHORDATA

CLASS =UROCHORDA= or =TUNICATA=

The most conspicuous animals of this class are the ascidians, which are common objects on rocky coasts. The /simple ascidians/ are peculiar leathery, sac-shaped bodies which send out jets of water when touched. This habit gives them the common name of "sea-squirts." Some are highly colored, especially those of Southern waters; others are somber, unattractive bodies, often growing in masses. The /compound ascidians/ are gelatinous colonies, sometimes forming thin incrustations, sometimes jelly-like masses, on seaweeds, shells, etc. This class comprises also the beautiful /Salpa/, a genus of free-swimming animals having transparent bodies encircled by rings of muscular bands, and in one stage forming chains of attached organisms which swim on the surface of the sea and of bays.

The tunicates are by some authors classed with the vertebrate animals because in the larval stage they have a notochord; this disappears, however, in the adult form, and the animals are considered degenerates. The tunicates are interesting to biologists from the remarkable changes they undergo in their life-history, and (in some genera) the marked phase of alternation of generation. One of their curious anatomical features is the blood-vascular system. The circulation is propelled by wave-like contractions of the heart, which, after forcing the blood one way for a time, stops and reverses the blood-current. The tunicates are widely distributed, and occur at all depths. (Plate LXXXV.) [pg475]

GENUS ^Salpa^

The animals of this genus are transparent, subcylindrical, smooth, gelatinous bodies encircled by bands of white muscular fiber. They strikingly exemplify alternation of generations. They occur in two distinct conditions, one being solitary, the other consisting of animals united in chains. The solitary individuals are about an inch long, and have two long processes at the posterior end. These single animals reproduce by budding, and form series of individuals in small chains, the animals being arranged in two rows. The chains grow to the length of a foot or more, and contain twenty to thirty pairs of salpas. Each of these connected individuals produces in turn a single egg, which becomes a single /Salpa/, and this again, like its grandmother, reproduces by budding. Thus the animals are alike only in alternate generations. The naturalist Chamisso, who discovered the relationship between the two forms, expressed it as follows: a /Salpa/ mother is not like its daughter or its mother, but resembles its sister, its grandmother, and its granddaughter. The single zooeids liberate many colonies during the summer, which grow rapidly, and in the autumn the chains are exceedingly abundant. The /Salpa/ chains swim about with a serpentine movement, and are beautiful, delicate objects with their transparent bodies banded with white, tinged with pink, and streaked with blue.

SIMPLE ASCIDIANS

These are solitary and usually fixed; they are never free-swimming, and when in colonies each animal has a distinct test. All the larger ascidians, or sea-squirts, belong to this group.

GENUS ^Molgula^

Body more or less globular, membranous, attached or free; orifices on very contractile tubes.

^M. manhattensis.^ Nearly globular when the tubes are contracted;
usually covered with bits of eel-grass, seaweeds, sand, etc.;
surface a [pg476] little rough; color olive-green. The animal is
often attached to rocks, more frequently to eel-grass and seaweeds,
and is sometimes so crowded as to form large clusters. Found from
Maine to North Carolina.

^M. pellucida.^ Body nearly globular, about an inch in diameter,
smooth, clean, and translucent, the intestine showing through the
test. The two tubes are large, swollen at the base, and divergent.
The animal lives free in the sand, and is found from Massachusetts
to North Carolina.

^M. arenata.^ Body somewhat compressed laterally; test thin and
covered completely with sand, which is closely adherent; about
three quarters of an inch in diameter; tubes short and wide apart.
Found on shelly and sandy bottoms of bays and sounds.

GENUS ^Cynthia^

The animal is attached, the body coriaceous, and the orifices four-lobed. Frequently associated in groups, the individuals often differing in color.

^C. pyriformis.^ Body globular, or oblong when extended; hard,
velvety, whitish surface, with pink cheeks; orifices on prominent
protuberances on the upper surface. It lives in clear, deep water
on rocks, and is sometimes found at low-water mark on the northern
New England coast. Commonly called the sea-peach. (Plate LXXXV.)

^C. partita.^ Body oblong; attached; test horny and wrinkled;
rusty-brown; apertures square, on prominent tubes marked with
triangular spots of white and purple; diameter one inch. Found on
the piles of wharves and on shelly bottoms in shallow water; also
on the under side of stones when they are much flattened.

^C. carnea.^ Test low and flat, with a thin margin; adherent by a
very broad base; orifices small, square, slightly prominent; red
or flesh-color. Found in deep water on stones and shells on the
northern New England coast.

GENUS ^Boltenia^

Body more or less globular, on a long stem; fixed; orifices on the side.

^B. clavata.^ Body long, wrinkled, leathery, on a long stalk,
resembling the flower of lady's-slipper (/Cypripedium/); two
cross-shaped orifices wide apart on the side; yellowish in color;
attached to stones in deep water, but sometimes washed ashore in
storms. The stalks are often covered with polyzoans and hydroids.
(Plate LXXXV.)

GENUS ^Ascidia^

Test gelatinous or cartilaginous; attached; it grows in bunches under stones at low-water mark. Sometimes it is variously [pg477] colored, but otherwise it is repulsive in aspect. The apertures are wide apart; one orifice is eight-lobed, the other six-lobed.

^A. amphora.^ Form usually globular, but more or less irregular;
substance something like rubber. Found of all sizes adhering in
clusters to stones, shells, and piles, and usually covered with
marine growths. The color is grayish-brown.

^A. callosa.^ Body depressed, usually oval, but varying in shape;
thick, fleshy, translucent; surface uneven; apertures dark purple
and prominent. Found at low tide adhering to stones and shells.
(Plate LXXXV.)

COMPOUND ASCIDIANS

Ascidians of this group form fixed colonies, and are embedded in gelatinous material, the animals having a common test, but not being united by any internal union. The colonies thus formed are flat and incrusting, or are branched and lobed, or sometimes elevated on stalks. The zooeids are in some cases dotted irregularly over the entire surface, in others are in rows, or again are in groups. They have various colors--purple, yellow, blue, gray, and green. They are common on eel-grass, the piles of wharves, the bottoms of boats, and so on.

GENUS ^Botryllus^

^B. gouldii.^ This species forms thick, fleshy, translucent
incrustations, often several inches in length and a quarter of an
inch wide, over eel-grass, the piles of wharves, and other objects.
Sometimes, at the end of summer, small objects are completely
covered with the luxuriant growth of this compound ascidian. The
zooeids form circular or elliptical groups, often as many as fifteen
surrounding each orifice, looking like minute stars. The colonies
vary in color. Often on the same stem of eel-grass will be found
separate colonies varying in this respect. In some the ground-color
will be olive-green specked with white, while the zooeids are
purple, marked with other colors; again the arrangement is quite
different.

GENUS ^Amaraecium^

^A. pellucidum.^ A massive compound ascidian, smooth, translucent,
and gelatinous, which forms large, hemispherical, complex,
irregular masses six inches or more in diameter. It is usually
covered by adhering sand. The mass consists of club-shaped lobes,
which rise from a common base. Each lobe contains a central orifice
around which long, slender zooeids, sometimes an inch long, are
grouped. These masses are so abundant in some places that they
cover the bottom for considerable spaces. They are found in deep
water from Cape Cod to North Carolina. [pg479]

INDEX

Heavy-faced type is used to indicate names of classes, orders, genera, etc.; heavy-faced numerals to indicate the place where the fullest description is given

A

Abdomen, 243, =246=.

Abductor muscles, =302=.

Aboral, 202.
Surface, 201.

Abyssal, =23=.

Acalephs, =134=.

=Acanthalithodes=, 240, =271=.
=A. hispidus=, 240, =271=.

=Acephala=, 409.

=Acetabularia=, 51, =57=.
=A. crenulata=, 51, =57=.

=Acmaea=, 9, 309, 312.
=A. mitra=, 324, =357=.
=A. patina=, 324, =357=.
=A. testudinalis=, 41, 42, 324, 343, 348, =356=.
=A. testudinalis=, var. =alveus=, 324, =357=.

=Acmaeidae=, 324, 356.

Acontia, =145=.

Acorn-shell, =254=.

=Actiniaria=, 141, =142=, 143, 144.

=Actinozoa=, 112, 115, 141, =142=.

=Adamsia palliata=, 144, =267=.

Adductor muscles, =302=, 413, 417.

=AEolididae=, 324.

=AEolis=, 41, 42, 309, 324, =354=.
=AE. papillosa=, 324, =354=.

=AEquoreidae=, 116, =128=.

=AEtea=, 188, =194=.
=AE. anguinea=, 188, /194/.

=Agarum=, 36, 42, 63, 68, =69=.

=Aglaophemia=, =127=.
=A. struthioides=, 116, =127=.

=Ahnfeldtia=, 76, =82=.
=A. plicata=, 76, =82=.

=Alaria=, 63, =69=.
=A. esculenta=, 41, 42, 63, =69=.

=Albunaea=, 240, =269=.
=A. gibbesii=, 240, =269=.

=Alcyonacea=, 141, =151=.

=Alcyonaria=, 141, 142, =150=, 152.

=Alcyonidium=, 189, 192, =197=.
A. hirsutum, 189, =197=.
=A. hispidum=, 189, =198=.
=A. parasiticum=, 189, =198=.
=A. ramosum=, 189, =197=.

=Alcyonium=, 141, =151=.
=A. palmatum=, 141, =150=, 161.

Aleutian province, =311=.

=Algae=, =25=, =48=, 62, 76.
Botanical facts about, =25=.

Alternation of generation, =120=, 121.

=Amar[oe]cium=, 473, =477=.
=A. pellucidum=, 473, =477=.

Ambulacra, 201, 202, =205=, 214, 218.

Ambulacral groove, 205.
Ossicles, =205=.
Zones, 201, 202, =205=, 218, 229.

American division, =24=.

=Amphictenidae=, 162, =183=.

=Amphineura=, 300, 316, 317, 320, =321=, 323.

=Amphipoda=, 242, =289=.

=Amphissa=, 312.
=A. corrugata=, 326, =389=.

=Amphitrite=, 161, =182=.
=A. ornata=, 161, =182=.

=Amphiura=, 213, =215=.
=A. squamata=, 213, =215=.

Ampullae, 201, =205=, 206, 218.

=Anadyomene=, 51, =57=.
=A. flabellata=, 51, =57=.

Anatomy, 20.
Of higher Crustacea, =246=.

Anemone Cave, =40=.

Angel's-wings, 461.

Animal-flowers, =142=.

Animal life in its lowest forms, =21=.

=Annelida=, 305.

=Annulata=, 159, 161, 164, 170.

=Anomia=, 405, =424=.
=A. aculeata=, 405, =425=.
=A. lampe=, 405, =425=.
=A. simplex=, 405, =424=.

=Anomiidae=, 405, =424=.

=Anomura=, 240, =264=.

Antennae, 243, =246=, 258.

Antennules, 243, =246=, 258.

=Antheneidae=, 204, =209=.

=Anthomedusae=, =116=.

Aperture, =302=.

Apex, 343.

=Aphrodite=, 161, =174=.
=A. aculeata=, 161, =174=.

=Aphroditidae=, 161, 172, =173=.

=Aplacophora=, 300, 321, =323=.

=Aplysella violacea=, 105.

=Aplysia Wilcoxii=, =352=.

=Aplysiidae=, 324.

=Apoda=, 228, =233=.

=Appendicularia=, 472.

=Arabella=, 161, =179=.
=A. opalina=, 161, =179=.

=Arbacia=, 217, =222=.
=A. punctulata=, 217, =222=.

=Arbaciadae=, 217, 222.

=Arca=, 310, 405, =425=.
=A. noae=, 405, =426=.
=A. pexata=, 405, =425=.
=A. ponderosa=, 405, =426=.

=Arcachon=, 434.

=Architeuthis=, 465.

=Arcidae=, 405, =425=.

Arctic province, =309=.

=Arctica=, 406, =441=.
=A. islandica=, 406, =441=.

=Arenicola=, 162, 172, =184=.
=A. marina=, 162, =184=.

=Arenicolidae=, 162, =184=.

=Argonauta=, 464, 467, 468.
=A. argo=, 464, =469=.

Aristocratic genera, 313, 377, 398, 401.

Aristotle's lantern, =203=.

=Arthrocladia=, 62, =67=.
=A. villosa=, 62, =67=.

=Arthropoda=, 238, =244=.

=Arthrostraca=, 242, =289=.

=Articulata=, 188.

=Ascidia=, 473, =476=.
=A. amphora=, 473, =477=.
=A. callosa=, 473, =477=.
=A. compositae=, 473.
=A. simplices=, 473.

=Ascidiacea=, 473.

Ascidians, 8, 474.
Compound, 474, =477=.
Simple, 474, =475=.

=Ascophyllum=, 63, =73=.
=A. nodosum=, 43, 63, 73.

=Asperococcus=, 62, =66=.
=A. echinatus=, 62, =66=.

=Astacoidae=, 240, =261=.

=Astarte=, 309, 406, =440=.
=A. castanea=, 406, =441=.
=A. undata=, 406, =441=.

=Astartidae=, 406, =440=.

=Asterias=, 204, =212=.
=A. Forbesii=, 204, 207, =212=.
=A. gigantea=, 204, 207, =212=.
=A. ochracea=, 204, =212=.
=A. vulgaris=, 43, 204, 207, =212=.

=Asteriidae=, 204, =212=.

=Asterina=, 204, =210=.
=A. folium=, 204, =210=.
=A. miniata=, 204, =211=.

=Asterinidae=, 204, =210=.

=Asteroidea=, 200, 204, =205=.

=Astraea=, 141, 146, 147, =148=.

=Astrangia=, 141, =150=.
=A. danae=, 13, 141, =150=.

=Astropecten=, 204, =209=.
=A. articularis=, 204, =209=.

=Astropectinidae=, 204, =208=.

=Astrophyton=, 213, =215=.
=A. Agassizii=, 213, =215=.

=Astyris gausapata=, 326, =389=.

=Asymmetrical=, 328.

=Aurelia=, 133, =137=.
=A. flavidula=, 133, =137=.

=Auricula=, =231=.

=Auriculata=, 201.

=Avicula=, 405, =431=.
=A. atlantica=, 405, 431.

=Avicularia=, 190, =193=.

=Aviculidae=, 405, =430=.

B

=Balanus=, 239, 250, =254=.
=B. balanoides=, 239, =255=.
=B. crenatus=, =256=.
=B. eburneus=, 239, =255=.
=B. geniculatus=, 239, =256=.
=B. ovularis=, =255=.
=B. rugosus=, 239, =256=.
=B. tintinnabulum=, 239, =256=.

=Bangia=, 78, =96=.
=B. fusco-purpurea=, 43, 78, =96=.

=Bangiaceae=, 78, =96=.

Barnacles, 8, 43, 245, =250=.

Bathymetrical division, 23.

=Bdelloura=, 160, =167=.
=B. Candida=, 160, =167=.
=B. rustica=, 160, =167=.

Beach-flea, 245, =289=.

Beak, 417.

=Bela=, 309.

Benthos, =23=.

=Beroida=, 154, =157=.

Bilateral symmetry, 20, 302, =320=, 321.

Binomial nomenclature, 28.

=Bipinnaria=, 201.

Biramous, =243=, 257.

=Bittium=, 326, =374=.
=B. nigrum=, 326.

Bivalves, =306=, 307, 314, 315, 409.
Mud-boring, 452.
Rock-boring, 452, 460.

Blastostyles, =120=.

Blue crab, 275.

Blue-green seaweeds, 47, 48, 49.

Body-whorl, 304, =343=.

=Bolina=, 154, =156=.
=B. alata=, 154, =156=.
=B. septentrionalis=, 154, =156=.
=B. vitrea=, 154, =156=.

=Boltenia=, 473, =476=.
=B. clavata=, 473, =476=.

=Bopyridae=, =292=.

Boreal, 23.

Boring amphipod, 290.

Boring-sponges, 105.

=Bostrychia=, 77, =89=.
=B. rivularis=, 77, =89=.

Botanical facts about algae, =25=.

=Botryllus=, 473, =477=.
=B. gouldii=, 473, =477=.

=Bougainvillea=, =124=.
=B. superciliaris=, 116, =124=.

Box-crab, =287=.

=Brachyura=, 241, 258, =272=.

Brain-corals, 146.

Branchiae, 302, =319=, 329, 336, =413=.
Dermal, 208.

=Branchiolaria=, 201.

=Brissopsis=, 217, =227=.
=B. lyrifera=, 217, =227=.

"Brit," =249=.

Brittle-stars, 43, 200, =214=.

Brown bodies, 190, =193=.

=Bryopsis=, 51, =59=.
=B. plumosa=, 51, =59=.

=Bryozoa=, =191=.

Buccal mass, 302, =317=.

=Buccinidae=, 327, =391=.

=Buccinum=, 12, 309, 313, 327, 330, =392=.
=B. undatum=, 42, 44, 314, 327, 331, =392=.

=Bucidium parasiticum=, 144.

=Bugula=, 188, 192, 193, =195=.
=B. flabellata=, 188, =196=.
=B. Murrayana=, 188, =196=.
=B. turrita=, 43, 188, =195=.

=Bulla=, 324, =351=.
=B. nebulosa=, 324, =351=.
=B. occidentalis=, 324, =351=.
=B. solitaria=, 324.

=Bullidae=, =324=.

Butterfly-shells, =323=.

=Byssus=, =415=, 426, 432.

C

=Caberea=, 188, =195=.
=C. Ellisii=, 188, =195=.

Cake-urchins, 218, =224=.

=Calappa=, 241, =287=.
=C. flamma=, 241, =287=.

=Calappidae=, 241, =287=.

=Calcarea=, 100, =104=, =106=.

Calcareous hydroids, =129=.
Seaweeds, =31=, 147.

Californian province, =312=.

=Callinectes=, 241, =275=.
=C. hastatus=, 12, =275=.
=C. sapidus=, 241, 274, =275=.

=Calliostoma=, 312, 325, =361=.
=C. annulatum=, 325, =361=.
=C. canaliculatum=, 325, =361=.
=C. costatum=, 325, =361=.
=C. jujubinum=, 325, =361=.
=C. occidentale=, 325, =361=.

=Callista=, 311, 410.
=C. gigantea=, =450=.
=C. maculata=, =450=.

=Callithamnion=, 15, 78, 79, =90=.
=C. americanum=, 78, =90=.
=C. Baileyi=, 78, =91=.
=C. byssoideum=, 78, =91=.
=C. floccosum=, 78, =91=.
=C. Pylaisaei=, 78, =91=.
=C. seirospermum=, 78, =91=.

=Callophyllis=, 76, =82=.
=C. laciniata=, 76, =82=.
=C. variegata=, 76, =82=.

=Calothrix=, 48, =49=.

Cameo-cutting, =381=.

Campanularians, 116, 121, =125=.

Canal, 302.
Anterior, =344=.
Posterior, =344=.
System of sponge, 103.

=Cancellaria=, 310, 327, =402=.
=C. reticulata=, 327, =402=.

=Cancellariidae=, 327, =402=.

=Cancellus=, =266=.

=Cancer=, 241, =277=.
=C. antennarius=, 241, =280=.
=C. borealis=, 241, =277=.
=C. irroratus=, 241, =277=.
=C. magister=, 241, =278=.
=C. productus=, 241, =278=.

=Cancroidae=, 241, =277=.

=Caprella=, 8, 242, =291=.
=C. geometrica=, 242, =291=.

=Capulidae=, 325, =369=.

Carapace, 243, =246=.

=Carcinides=, 241, =274=.
=C. maenas=, 241, =274=.

=Carcinus maenas=, 41, =274=.

=Cardiidae=, 407, =453=.

=Cardita=, 406, =440=.
=C. borealis=, 406, =440=.
=C. floridana=, 406, =440=.

=Carditidae=, 406, =439=.

=Cardium=, 310, 311, 407, 410, 413, =453=.
=C. corbis=, 407, =454=.
=C. elatum=, 407, =454=.
=C. islandicum=, 407, =454=.
=C. isocardia=, 407, =454=.
=C. laevigatum=, 407, =454=.
=C. magnum=, 407, =453=.
=C. mortoni=, 407, =454=.
=C. pinnulatum=, 407, =454=.
=C. quadrigenarium=, 407, =454=.
=C. serratum=, 407, =454=.
=C. substriatum=, 407, =454=.

Caribbean province, 310.

Carinated, 302.

Cartilage, =417=.

Cartilaginous, 27.

=Cassididae=, 326, 380.

=Cassiopeia=, 133, =140=.
=C. frondosa=, 133, =140=.