402 PROCEEDINGS OF THE ACADEMY OF [1892. 



were written each in complete ignorance that the other was engaged 

 upon the group in question. 



The present genus, therefore, is the product of our independent 

 labors, and is equivalent to Charojndce Hedley phis Gerontia Pils- 

 bry. It therefore includes Phenacoheiiciclce Suter and Charopidce 

 Hutton. 



The choice of the name Endodonta for the genus is inevitable, as 

 it is the oldest proposed. The following groups seem to belong 

 here : 



Endodonta s. sir. (+ Pitys Pse. non Beck). 



Libera Garrett. 



Diaglyptns Pils. (? ? = Pitys Beck, never defined). 



Sim-plicaria Mouss. (== toothless Endodonta'). 



Maoriana Suter (Huttonella Suter, preoc). 



JEschrodo7mis Pils. (= Thera Hutt., preoc). 



CharopaAlh. 



Gerontia Hutt. 



Therasia Hutt. 



Calymna Hutt, (plus Amphidoxa Hutt. non Alb.). 



Pyrrha Hutt. 



Phenacohellx Suter (= Fruticicola Hutt. non Held). 



Allodiscus Pils. (= Psyra Hutt., preoc). 



Suteria Pils. (= Patnlopsis Suter, non Strebel). 



Thalassohelix Pils. (= Thalassia of N. Z. authors 7ion Alb.; not 

 Thalassia Chevrolat). 



Phacussa Hutt. 



Genus PATULA Held. 



Genital system lacking all accessory appendages. Jaw vertically 

 striated. Marginal teeth multicuspid. 



This genus includes the typical forms of Europe and America 

 (Discus, Angwisplra, Pyramidula, Gonyodiscus), and also the subgenus 

 Helicodiscus Morse. Perhaps Zoogenites Morse. Various forms 

 of this genus are found in most parts of the world, except Ocean- 

 ica, Australia, etc 



Genus TROCHOMOKPHA. 

 Semper, Reisen im Archip. Phil., Landmoll. 



Distinguished from Patula, etc., mainly by the keeled and other- 

 wise very different shell and the differently shaped marginal teeth 

 of the radula. 



