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Show 310 MR. F. F. LAIDLAW ON THE [Apr. 21, Family C r y p to c e l id id ^e . B e r g e n d a l ia a n om a l a , gen. et sp. nov. (Plate XXIII. figs. 4, 5, 6, & 8.) A most remarkable and interesting form, probably allied to the anomalous genera Cryptocelides and Polypostia, described by Bergendal [1], and provisionally referred to the same family with them. The structure of the female terminal ducts is, so far as I know, unique, and approached only by the species referred to Trigono-porus and Polyporus (see von Plehn [11]). Only a single specimen was obtained. It is rather a large form, with a total length of about 60 mm. and breadth about 27 mm. The mouth-opening is some 15 mm. from the hind end, and the genital pores lie halfway between these two points. The margin of the body is complete, surrounded by a continuous rather dense row of eye-spots. There are none of these, apparently, over the brain. Colour in the spirit-specimen uniformly greyish white (see PI. XXIII. fig. 8). The specimen appears to be in an early stage of sexual maturity, since no trace of ovaries or testes can be discovered. The pharynx is large and much folded, the gut-branches are numerous and anastomose freely. The cells of the epidermis are elongated, especially on the dorsal surface. True rhabdites are absent, but in place of them the epidermal cells are crowded with pseudorhabdites which are of a coarsely granular texture, faintly stained and columnar in shape. In my sections (stained with Grenadier's hsematoxylin) certain gland-cells lying within the muscle-layers of the body-wall, especially on the ventral side, are deeply stained; from these cells run processes which pierce the muscle-layers and basement-membrane, and make their way to the surface through the epidermal cells. These deeply-lying gland-cells and their processes have rather a spongy appearance, due to their preservation not being quite perfect. Genital Organs (text-fig. 54, p. 311). The penis (p.) is a small fleshy organ composed of nucleated longitudinal fibres (PI. XXIII. fig. 4). Its outer side is lined with cells continuous with those lining the antrum masculinum, but whereas the latter are ciliated, those covering the penis are non-ciliated. The base of the penis is pierced by a duct running nearly vertically upwards. Immediately after leaving the penis this is joined by two small ducts-the vasa deferentia (v.d.)- which run forward on either side of the middle line. In one of them, at the level of the hinder end of the pharynx, there is a slight dilatation containing spermatozoa. The vesicula (p\) lying above the penis is small. Its wall |
