24 ON THE ANATOMY OF SOME TASMANIAN SNAILS, 



Helicarion verreauxi, Pfeiffer. 



This is the southernmost member of its genus, the "enfant 

 perdu" of its race. The other species that have been associated 

 with it, fumosa, Tenison-Woods, and milligani, Pfeiffer, may be 

 referred to Paryphanta until their position be authoritatively- 

 decided by scalpel and microscope. Like B. dufresni and R. 

 lampra, this species ranges over the entire island, hiding in dry 

 weather under logs and stones. The animal measures 37 mm. in 

 total length, resembles in form the continental species, //. robustus, 

 Gould, and H. hyalinus, Pfr., but differs in colour, the entire 

 body being coal black with the exception of the tail, whose 

 extremity is lemon-yellow. The jnw is arcuate, with central 

 projection, smooth, ends rounded. The radula consists of 130 

 rows of 70-17-1-17-70 ; the rachidian is broadly reflected and 

 overlaps the basal plate laterally for more than half its length, 

 then is divided into a slender lanceolate median cusp exceeding in 

 length the basal plate and two small accessory cusps with well 

 developed cutting edges ; the laterals have the outer posterior 

 margin of the basal plate very short and square, the main cusp is 

 slightly larger than that of the rachidian and bears at its outer 

 base a well developed accessory cusp, which increases as the teeth 

 retreat ; the marginals possess slender inclined knife-like cusps 

 which become bind as the border of the ribbon is approached. 

 As regards the genitalia, the penis-sac is long and slender, twisted 

 into a figure of eight, and terminating in a round knob, retractor 

 muscle inserted on the distal curve of the 8 ; vas deferens con- 

 torted on its departure from the prostate ; spermatheca large, 

 slightly dilated, acuminate above, connected with the genital 

 system by a short wide duct. 



Cystopelta petterdi, Tate. 



A figure and description of this mollusc will be found in the 

 preceding volume of these Proceedings (PI. i., p. 44). I took the 



