BY C. HEDLEY. 691 



Radula (pi. xxxix., fig. 18), formula 104 rows of 33 : 6 : 1 : 6 : 33 ; 

 rachidian cusp stout, ovate, two-thirds the size of the first lateral, 

 extending along more than half of its basal plate ; the cusp of the 

 first lateral is large, oval, blunt, much inclined and equalling or 

 surpassing the posterior margin of its basal plate, the succeeding 

 laterals diminish in size ; they are followed without any transition 

 teeth by the marginals, which acquire a distal cusp in the same 

 plane as the chief cusp and a falcate proximal cusp on a higher 

 plane. 



Genitalia (pi. xli., fig. 26), penis sac subcylindrical; spermatheca 

 oval on a long peduncle. 



Succinea simplex, Pfeifier. 



Jaw (pi. xlii., fig. 34) ribless, with a blunt median inferior 

 projection, ends recurved. 



Radula (pi. xlii., fig. 37) narrow, strap-shaped, three times as 

 long as broad ; formula 85 rows of 16:13 : 1 : 13 : 16 ; rachidian 

 with basal plate twice as long as broad, slightly expanded poste- 

 riorly, reflection small, tricuspid, main cusp ovate, extending 

 halfway along the basal plate, accessory cusps about half the size 

 of the parent ; laterals bicuspid, the proximal twice as long as the 

 distal but shorter than the basal plate, which is emarginate on its 

 posterior edge ; one transition tooth is followed by minute mar- 

 ginals with trificl or quadrifid cusps. 



Since writing the previous paper, several parts of the " Manual 

 of Conchology " have appeared. Had I received them earlier, I 

 should have profited by much additional information, and have 

 replaced Geotrochus by Papuina, transferred rehsei and beatricis 

 from Hadra to Chloritis, also bevani, oxystoma and elisus from 

 Geotrochus to Obba, and reduced tapparonei to a synonym of P. 

 naso, von Martens. I find that S. gracilis, Hutton, has several 

 years' priority over S. subtcla, Pfr. (ante, pp. 98 and 557). 



In alluding (ante, p. 100) to S. simplex, I expressed a doubt as 

 to the correctness of the determination. Having requested Mr. 

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