238 PROCEEDINGS OF THE ACADEMY OF [1895. 



able excuse for reviving Ferussac's term Helicteres, for it was not 

 intended as a generic or sub-generic name by Ferussac, and is 

 improper in form. Its use would open the door to an endless series 

 of vagaries in nomenclature, as any one who examines Ferussac's 

 original publication may see. 



2. Genus Leptacnatina Gould, 1848. Contains Amastra, New- 

 combia, etc. 



3. Genus Carelia H. and A. Ad., 1855. 



The relationships of these genera and their subgenera will prob- 

 ably be decided by a study of their genitalia, which the writer hopes 

 to undertake later; and these data will also aid in deciding whether 

 the Achatinellidse constitute a separate family, or are merely a 

 division of Achatinidse. 



The following notes materially increase the list of species of which 

 the dentition is known, and tend to strengthen the views advanced 

 by Binney in the publications noticed above. 



The Dentition of the Achatinella. By H. M. Gwatkin. 



Molluscous radulse are in general fairly uniform in the species of a 

 genus, and form a very trustworthy character. The chief anomalies 

 are in a few families like the Buccinichv, where the individual varia- 

 tion is greater than the specific, and in a few species where radulse of 

 two or more types are found, like Phasianella and Calliostoma among 

 the marine genera, B'ulimidus and Cylindrella among the terrestrial. 



Achatinella is a conspicuous instance of the latter class. We find 

 in it two well-marked and very distinct types of radula, viz.: 



(a). Jaw missing, radula broad, oblong, teeth very numerous, 

 en chevron (rows sloping obliquely backward). Centrals (if present), 

 laterals and marginals, all of the same type: Base narrow, head 

 rather* broad, with four, five, six or seven small tentacles (exactly as 

 in Janella and Tornatellina and the marginals only of Siicchiea). 



To this section belong : 



Achatinella *nivea Bald. 



A. *Anceyana Bald. 



A. *bella Rve. 



A. *canaliculata Bald. 



A . cinnamomea Pfr. 



A. Dwightii Newc. 



A. eburnca ( Jul. 



.1. *JHawaiiensis Bald. Formula. 



l23—l2- r > x. 120=30,120 

 A. Hbrneri Bald. 

 A. marmorata Gld. 



A. *Mighelsiana Pfr. 



A. Natti Bald, and Hartm. 



A. perdix Rve. 



A. proxima Pse. 



A. *pulcherrima Swains. 



A. Bedfieldii Newc. 



.1. rhodoraphe Sin. 



A. silica hi Pfr. 



A. Hessellata Newc. 



A. *virgulata Migh. 



Auriculella brunnea Smith. 



