Chapter XIV: Kerona

Vermis inconspicuus corniculatus. An invisible worm with horns.

260. KERONA RASTELLUM. K. orbicularis membranacea, nasuta, corniculis in tota pagina. Membranaceous, orbicular kerona, with one projecting point, the upper surface covered with small horns. There are three rows of horns on the back, which nearly occupy the whole of it. It was found in river water.

261. KERONA LYNCASTER. K. subquadrata, rostro obtuso, disco corniculis micantibus. This species of kerona is rather square, and its disc furnished with shining horns. See Zool. Dan. prod. add. p. 281.

262. KERONA HISTRIO. K. oblonga, antice punctis mucronatis nigris, postice pinnulis longitudinalibus instructa. Plate XXVII. Fig. 20.

It is an oblong membrane, pellucid, with four or five black points in the fore-part, which are continually changing their situation, thick set with small globules in the middle, among which four larger ones are sometimes perceived, these are probably eggs; in the middle space of the hind-part are some longitudinal strokes resembling bristles, which, however, do not seem to project beyond the body. _b_, the horns; _c_, some hairs; _d_, a solitary horn; _e_, a large globule; _f_, some bristles.

263. KERONA CYPRIS. K. obovata, versus postica superne sinuata, antice crinita. Plate XXVII. Fig. 21. Egg-shaped, towards the hind-part sinuated, the fore-part hairy.

This animalculum is compressed, and somewhat of a pear-shape; the fore-part broad and blunt; the front is furnished with short hairs or little vibrating points inserted under the edge _a_, shorter in the hind-part _e_, partly extended straight, and partly bent down, having a retrograde motion. It is found in water which is covered with lemna.

264. KERONA HAUSTRUM. K. orbiculata, corniculis mediis, antice membranacea ciliata, postice setosa. Orbicular kerona, with the horns in the middle, the fore-part membranaceous and ciliated, and several bristles at the hinder-part.

265. KERONA HAUSTELLUM. Differs from the preceding only in having the hinder-part without any bristles.

266. KERONA PATELLA. K. univalvis, antice emarginata corniculata, postice setis flexilibus pendulis. Plate XXVII. Fig. 22 and 23. Kerona with a univalved shell, orbicular, crystalline; the fore-part somewhat notched; the fleshy body lies in the middle of the shell; above and below are hairs or horns of different lengths jutting out beyond the shell, and acting instead of feet and oars, some of which are bent; the superior ones constitute a double transverse row. _a_, the fore-part; _b_, the horns; _d_, a lunated figure in the shell; _c_, a pulpous body; _f_, bristles at the hinder-part.

267. KERONA VANNUS. K. ovalis subdepressa, margine altero flexo, opposito ciliato, corniculis anticis, setisque posticis. Oval and rather flat kerona, with one edge bent, the opposite one ciliated, the front furnished with horns, and the hind-part with bristles.

268. KERONA PULLASTER. K. ovata, antice sinuata, fronte crestata, basi crinita. Plate XXVII. Fig. 24 and 25. Oval, the fore-part sinuated, a crest on the front, the base hairy.

It agrees in many respects with the trichoda pulex, No. 252; but the upper part is pellucid, without any black molecules; the front truncated, the whole surface of the head covered with hair, and the fore-part sinuous. _a_, the horns; _b_, the hairs at the hinder-part; _c_, the cilia of the front.

269. KERONA MYTILLUS. K. subclavata, utraque extremitate latiori, hyalina ciliata. Plate XXVII. Fig. 29. Rather clubbed, broad at both extremities, clear and ciliated.

A large animalculum, the fore and hind-part rounded, very pellucid and white, dark in the middle, with black intestines, intermixed with a few pellucid vesicles; both extremities appear as if composed of two thin plates. The fore-part is ciliated, the hairs short, lying within the margin; it is also ornamented with two small horns, erected from an obscure mass; with these it agitates the water, forming a little whirlpool. The hind-part is likewise ciliated, and furnished with two bristles, extending beyond the margin. _a_, the horns; _b_, the fore-part ciliated; _c_, the hind-part; _d_, projecting bristles.

270. KERONA LEPUS. K. ovata, apice crinito, basi setosa. Egg-shaped, the fore-part hairy, the base furnished with bristles.

The body is egg-shaped, compressed, pellucid, and crowned with short waving hairs, the base terminating with bristles.

271. KERONA SILURUS. K. oblonga, antice et postice crinita, dorso ciliato. Oblong, the fore and hind-part hairy, the back ciliated.

An oval smooth animalculum, somewhat crooked and opake, with a fascicle of vibrating hair on the fore-part; it has a sharp tail, furnished with unequal rows of moveable hairs, producing a rotatory motion; in the inside are some partly lucid, and partly opake points. The figure varies from oval to oblong, the filaments of the conferva are often entangled in the tail.

272. KERONA CALVITIUM. R. latiuscula, oblonga, antice corniculis micantibus. Rather broad, oblong, with glittering horns on the fore-part.

The body is rather broad and flat, both sides obtuse, filled with black molecules, and there is a dark spot near the hinder-part, where there are likewise a few short bristles. The interjacent vesicles are pellucid; no hairs on the fore-part, but instead thereof two little moveable horns, and from three to five moveable black points. It is found in the infusions of vegetables.

273. KERONA PUSTULATA. K. ovalis convexa, postice altero margine sinuata, utraque extremitate crinita, corniculisque anticis. Oval, convex, kerona, one edge of the hinder-part sinuated, both ends set with hairs, and some horns placed on the fore-part. This animalculum was found in salt water.