T. cymbiformis fulcata, antice et postice crinita. [Plate XXVII.] Fig. 17 and 18. Boat-shaped trichoda with furrows, the fore and hind-parts both hairy.
The body is oval; it resembles a boat as well in its motion as shape; the upper part is hollowed, the under part furrowed and convex; the stern round, with several hairs proceeding from it. It was found in salt water. Fig. 17, a, the head; b, the tail. Fig. 18, d, a pellucid bubble that is sometimes to be perceived.
258. Trichoda Cimex.
T. ovalis, marginibus lucidis, antice et postice crinita. [Plate XXVII.] Fig. 19. Oval trichoda, with a lucid margin, both the fore and hind-part hairy.
It is about the size of the trichoda lynceus, [No. 253], has an oval body, with a convex back, flat belly, and an incision in the margin of the fore-part, the edges of which incision appear to be in motion. Its intestines are pellucid and ill-defined. When it meets with any obstacles in swimming, it makes use of four small bristles, which are fixed to the under side, as feet. a, the hairs in the fore-part; b, the bristles at the hind-part; d, the back; e, two small projecting hairs; f, the substance to which the animalculum has affixed itself.
259. Trichoda Cicada.
T. ovalis, marginibus obscuris, antice et subtus crinita, postice mutica. Oval trichoda, with an obscure margin, the fore-part covered with hairs on the under side, and the hinder-part beardless.
It does not differ considerably from the preceding, though Müller has pointed out some shades by which they may be discriminated.
XIV. KERONA.
Vermis inconspicuus corniculatus. An invisible worm with horns.