24 PROCEEDINGS OF THE MALACOLOGICAL SOCIETY. 



(Figs. 10 to 12, ^.), in the region of which they open into the supra- 

 branchial chamber by well marked ciliated ducts. The animals were 

 evidently killed just about the breeding season, as they are full of ripe 

 spermatozoa, some of which had been discharged from the duct, 

 besides the ripe spermatozoa the tubules are full of yellowish globules, 

 which are probably nutritive in function and correspond with the 

 oil globules met with in the testes of other animals. 



The Alimentary Canal. — The mouth (Figs. 6 and 8, mo.^ opens 

 between the four labial palps, the union of the two anterior and two 

 posterior palps forming a kind of upper and lower lip ; passing from 

 the mouth is a well marked ciliated oesophagus, which in turn 

 communicates with a largo stomach (Figs. 6 and 10, s^.). The 

 digestive gland (Figs. 2, 5 and 9, /.) opens into the stomach through 

 two large bile ducts (right and left) ; this gland is a very large one, 

 and, besides ramifying round the oesophagus and stomach, extends 

 back for a considerable distance amongst the coils of the intestine. 

 The posterior portion of the stomach is elongated horizontally (Fig. 

 10, si^.), and the cilia reappear on its lining cells and indeed become 

 extremely long on the ventral surface ; they were wanting in its 

 anterior region owing to the presence of a thick protective secretion 

 Avhich covers the cells and projects freely into the cavity (this is the 

 ' ileche tricuspid' of Poll). From the postero- ventral region of the 

 stomach two tubes arise; the larger (Figs. 6, 10 and 11, cr.) on the 

 left is a conspicuously ciliated tube, it runs downwards and backwards 

 keeping close to the siirface of the body and finally ends blindly close 

 to the foot ; this cajcum from its position obviously represents the 

 crystalline-style sac, but in the specimens examined it contained no 

 secretion. The second opening out of the stomach is on the right side 

 and is much smaller ; it leads into a tube which, owing to the fact 

 that in the specimen before us it is empty, is of small calibi'o, although 

 in some specimens it was enonnously distended ; this is the first coil 

 of the intestine (Figs. 6 and 10, e.). The intestine, which is situated 

 entirely on the right side of the body, is only of moderate length and 

 very simple ; it runs obliquely downwards and backwards, and, after 

 making a slight twist or two, turns sharply forwards and ascends to 

 near the hinge, where it again bends abruptly backwards and runs to 

 the anus as the rectum, which is distinctly muscular and contracted 

 and consequently appears of small size. 



The Nervous System (Fig. 6) is very prominent, the cerebral, pedal 

 and visceral (parieto-splanehnic) ganglia being all of very large size; 

 these ganglia and their commissures have the typical relations as 

 exemplified in Anodon. A pair of minute otocysts (statocysts, Fig. 7) 

 were present on the upper side of either pedal ganglion ; each con- 

 tained a single large round otolith, and only occupied one section of 

 about -^V nim. in thickness. These were the only undoubted sense 

 organs that I was able to identify. 



All the aboA'e facts whicli I have pointed out tend to confirm Prof. 

 Tate's statement as to the affinities of this genus Avitli Galcomma and 

 Scintilla, and if we furtlier compare his description of the method of 

 progression of this form witli that of Galeomma, we shall see that in 



