﻿REVIEW OF FROG-SHELLS AND TRITONS 



1 ? I 



Monocirsus Cossmann, [903, seems more closely related to this 

 group than to Hilda with which he has placed it. h looks like a 

 precursor of Liiiatclla. 



Genus RANELLINA Conrad, 1865 



Type R. maclnrii Conrad. Claiborne Eocene. Synonym: Sanel- 

 lina Conrad, 1865, a typographical error. This type is extinct., so 



Ear as known. 



Genus AUSTROTRITON Cossmann, 1903 

 Type Triton radialis Tate. Tertiary of Australia. No recent 

 Triton has a protoconch such as is figured for this species by Mr. 

 Kesteven and 1 consider that it should be definitely separated from 

 the species he has associated with it on this ground alone, and most 

 of the Australian Tertiary species will naturally fall into the same 



gr< nip. 



The groups Plesiotriton Fischer, 1884, and Semitriton Coss- 

 mann. 1903, require further examination before they can he ad- 

 mitted to this family. Sections should he made, to demonstrate 

 whether there are really true plaits on the pillar lip, or whether the 

 so-called plaits are merely lirations connected with adult formations 

 about the aperture. In the former case Semitriton dennanti certainly 

 has much the aspect and even the nucleus of one of the Volutomi- 

 triiuc, or Volutocorbis. 



In this connection it may he added that the combination of Hindsia 

 (lyrata) with this family is of doubtful validity, though it is true 

 that a number of short tritons erroneously referred to Hindsia should 

 be placed here. The conchological characters are in some respects 

 quite similar, yet I believe that Nassaria or Hindsia was more cor- 

 rectly placed by Adams among the Rhachiglossa. A decision on this 

 question must await an examination of the radula. 



Triton scalariformis and convolutus of Broderip appear to be re- 

 lated to the Ranellas with irregular varices rather than to the present 

 family, as previously pointed out. They exhibit no indications of 

 being related to the Muricidce so far as the shells are concerned. The 

 operculum is not known to me. 



Genus GYRINEUM LINK, 1807 



Tvpe Murex gyrinus Linne (=Ranclla ranina Lam.). Recent. 

 Synonyms: Apollon Montfort, 1810, Cuvier, 1817, and Morch; 

 Gyrinea Morch, 1877: Apollo Fischer, 1883, Harris, 1897. 



This includes the Tritons with continuous lateral varices. Biplex 

 (perca Perry) Terry, is accepted as a section for species with the 



