156 Transactions. — Zoology. 



anteriorly. Perhaps this and the next species should form a distinct genus ; 

 certainly they do not belong to Physa. I would propose that Adams' sub- 

 genus Ameria be retained for them. 



BuLiMUs VARIABILIS, Gray (Physa). Animal and radula like B. gihhosa, 

 but with only 112 transverse rows of teeth. Teeth 18-1-18, of which seven 

 or eight are laterals. Generally the teeth are similar to those of B. gibhosa, 

 but the base of the central tooth is as broad as long at its posterior margin, 

 and the reflected portion is simply convex anteriorly ; the teeth are larger 

 and coarser, and the outer marginals are not so long. (PI. IV., fig. d.) 



This description is taken from the common species found in the neigh- 

 bourhood of Christchurch. It is very variable in shape, the whorls being 

 either rounded or slightly flattened behind ; the body whorl usually bears 

 indications of a keel, formed by a single row of fine short hairs, but some- 

 times this' is absent. The spire is more produced than in B. gihhosa, and 

 the whorls are not so much flattened behind as in P. mcesta. Whorls 4 ; 

 columella plait distinct. 



Probably the other species of Physa described from New Zealand will all 

 be found to belong to the same genus. 



Latia neeitoides. I have to thank Mr. T. F. Cheeseman for numerous 

 specimens, preserved in spirit, collected by him in Lake Pupuke, near Auck- 

 land. I have never seen the genus in the South Island. 



Animal. The eyes are at the outer bases of the tentacles, which, in 

 spirit specimens, are short, incurved, and transversely ringed. (PI. IV., 

 fig. u.) 



Dentition. There is no jaw. The radula is '08 inch in length, and "04 

 inch in breadth, the sides nearly parallel. There are 30 transverse rows of 

 teeth, which form an angle of about 115°, salient anteriorly. (PI. IV., 

 fig. p.) The teeth are 27-1-27. The central tooth is small, the reflected 

 portion half the length of the base, and bicuspid, but apparently without 

 any cutting points. The laterals are all nearly alike, and increase in size 

 outwards to about the sixteenth, and then diminish. The base is con- 

 stricted in the middle, and the outer side has two teeth near the posterior 

 end. The reflected part is oblique to the base, single cusped, with a 

 rounded cutting point. (PI. IV. fig. e.) 



The position of the eyes, outside the tentacles, would appear to take 

 Latia out of the LimnaidcB, and the absence of a jaw, as well as the arrange- 

 ment of teeth on the radula, are other characters by which it is distinguished. 

 It may form the family LatiidcB. 



Amphibola avellana. In a paper on the anatomy of this species, in the 

 "Ann. Nat. Hist." for 1879, I briefly described the dentition, but the des- 

 Qription is not sufficiently accurate^ and I have inadvertently stated that 



