36 CHELIDONURA, CRYPTOPHTHALMUS. 



The snail crawls slowly, the posterior appendages usually being 

 dragged straight out behind. On the front of the head on each lateral 

 lobe and the neighboring sinuses stood numerous peculiar sense 

 organs, appearing under the lens like bunches of bristles. They 

 consist of flexible conical tubes (fig. 34, x 25, and figs. 33, 35, 

 x 300) on the blunt distal ends of which is a bunch of many fine 

 hairs. The free end of the tubes can be drawn in. Under the 

 base of the bunch of hairs is an egg-shaped ganglion (fig. 35) in 

 which a nerve ends. The free end of the tube is exserted appar- 

 ently by its circular muscles, or perhaps by ingress of blood. 



C. ADAMSI Angas. Vol. XV, pi. 59, fig. 14. 



Head furnished in front with a short silky fringe ; mantle ter- 

 minating behind in two long bifurcate filaments, foot elevated on 

 each side, embracing the head and mantle, rounded both in front 

 and behind; color velvet-black, with a white crescent on the 

 hinder part of the mantle ; the head and the outer edge of the foot 

 are bordered with a line of brilliant blue ; a line of the same color, 

 bifurcated in front, extends down the back, and the posterior fila- 

 ments are ornamented in the middle with a similar line ; parallel 

 with these blue lines, and at a short distance from them, are lines 

 of a gold color ; and spots of the same appear above the white cres- 

 cent on the back, and at the bifurcation of the posterior filaments. 

 Shell internal, very small, thin, flat, with the right border termina- 

 ting in a point. Length 2 inches. (Aug.). 



Rock-pool at low water at Vancluse Bay, Port Jackson. 



C. adamsi ANG., P. Z. S., 1867, pp. 116, 227, pi. 13, f. 32. 



This species may be identical with the individual alluded to by 

 Quoy as having been met with at the Mauritius among numerous 

 specimens of his Sulla hirundinina, but which was not described by 

 him. I have named it in honor of my friend, Mr. Arthur Adams, 

 the founder of the genus Chelidonura. (Angas). 



Genus CRYPTOPHTHALMUS Ehrenberg, 1831. 

 Cryptophthalmus EHRENB. Symb. Phys. Evert. 



Shell internal, minute, white, fragile, the left margin incurved in 

 the middle, but not enrolled ; body whorl expanded, produced in a 

 pointed process above. 



Body elongated ; head shield small, truncate in front, bilobed be- 

 hind, bearing minute, sessile eyes on its anterior surface; foot as 



