2 , NUDIBRANCHIATE GASTEROPODA. 



seen to be longish-conical (fig. 3 b) and of a height of 3 mm . The dorsal margin projected, abont in 

 the same way as in Tritonia, and appeared to have been covered with branchial tnfts, resembling 

 those seen in that family, only a few ( — 4 mm high) remnants of these tnfts were left. The sides of 

 the body were as in Tritonia, rather high, and, on account of the projecting dorsal margin, a little 

 hollowed and sloping inward; in front the genital papilla was found in the common place as in Tritonia, 

 lure with the glans penis stretched forth; a little before the beginning of the last third of the length 

 of the body, and somewhat upward the anal papilla was seen projecting i-^ mm ; abont midway between 

 this and the genital papilla the minute renal aperture was seen. The foot is powerful; its fore end 

 (fig. 10) rounded, with a slight marginal furrow; the foot-brim of a breadth of up to 3 mm ; the back 

 and foot were coalesced quite to the point. 



The visceral cavity reached to the beginning of the last fourth of the length of the body. 

 The white (4 — 5 mm broad) central nervous system (fig. 12) showed the cerebro-pleural ganglia 

 to be roundish, connected with a quite short commissure, with no distinct bordering between the two 

 parts; the pedal ganglia scarcely smaller than the former, of an oval contour; the lower commissures 

 rather long (fig. 12 d). The buccal ganglia were of an oval contour, connected by a commissure, al- 

 most six times the length of the ganglion (fig. 12 e). 



The otocysts were situated behind the pleuro-pedal connective (figs. 12, 13) between the 

 ganglia; they had a diameter of o - i4 mm , and contained a few (ca. 10) clear, round, and oval otoconia of 

 a diameter of 0x335 — o - 04 mm . The skin had no larger spicules. 



The bulbus pharyugeus was large and powerful, somewhat resembling that in Tritonia, 

 but shorter, 6 n,m long by a height and breadth of 5 mm . In front it is (fig. 14) somewhat narrower, and 

 foremost on the upper side it is higher (on account of the hinge-part of the mandibles); behind this 

 projecting part the wide pharynx is found, and behind this the short and broad radula sheath (fig. 14); 

 the margin of the upper side corresponds to the outer margin of the mandible, and below this (above 

 on the side of the bulbus pharyngeus) a hollowing was seen. The labial disk is narrow; behind and 

 outside of it is found, quite as in Tritonia, the powerful muscular plate resting on the fore side of 

 the mandibles. These latter (figs. 14 — 17) are of a light amber-colour, 5*5 mm long by a breadth of 

 i-25 mm , at the hinder end of 2-25 mm ; the height of the convexity about 2 mm ; they were rather thin, 

 nor was the hinge-part thick, thinner as well as lighter in the outer hinder half (fig 17). The some- 

 what upwardly directed hinge-part is more narrow, the hinder end broader and emarginate in the 

 middle (fig. 16); a masticatory continuation was completely wanting, and the masticatory edge was 

 quite smooth throughout its whole length (fig. 17). The cheeks join the inside of the mandibles in 

 their whole length; only foremost in the little mouth-cavity a short stretch (fig. 14) of the hinge-part 

 of the mandibles is uncovered. The mouth cavity is almost quite filled out by the (highly contracted) 

 large, high, and broad tongue (figs 14, 18), the middle part of which is through its whole length 

 (fig. 18) covered by the light yellowish, rather broad radula, which farthest back continues in the 

 short and broad radnla-sheath (2 - 5 ram long, 4'5 ram broad) (fig. 14). The tongue has 21 series of teeth, 

 further back 12 series were seen, two of which were not yet fully developed. Thus the total number 

 of series of teeth was 33. The number of tooth-plates on either side of the median tooth rose to 120. 

 They were of a very light yellowish colour. The length of the median tooth-plates (on the hind 



