﻿I 1 8 SMITHSONIAN MISCELLANEOUS COLLECTIONS [ VOL. 47 



seems to have chosen types at random for the old names, as if none 

 had been selected before him. His arrangement thus applied the 

 old names to wrong groups, necessitating revision. The group con- 

 taining R. ventricosa Broderip, and R. califomica Hinds, he named 

 Crossata, to Lampas Schumacher (but not of the Museum Calon- 

 nianum) he gave the new name Tutu fa, and to the small Ranellas 

 with short anal tube, the name Lampasopsis later corrected by Fischer 

 to Lampadopsis. Fischer, in 1884, accepted in the main the arrange- 

 ment of Jousseaume, substituting Colubrellina for the name Colu- 

 braria Jousseaume non Schumacher. 



Cossmann, in 1903, returned to the point of view of Link and 

 Adams with results which cannot be regarded as happy. 



The Ranellas or Bursas shade very gradually into the forms for- 

 merly known as Triton or Tritonium, judged by most of their char- 

 acters, but the use of the anal sulcus as a distinctive character enables 

 us to differentiate the two groups. In preparing a key to the sub- 

 divisions of Bursa it was found necessary to propose two sectional 

 names, Marsupina for the restricted Buffo of Mont fort, and Chas- 

 motheca for the elegant Ranclla foliata of Broderip and its allies. 

 Those who prefer to consider species in large masses will properly 

 ignore the sectional divisions, but others will find the closer sub- 

 divisions convenient on many occasions, and, since several of them 

 were named by authorities so respectable as Lamarck and Fischer, 

 I have been tempted to make the system symmetrical. The following 

 key will enable any one to refer any of the true Bursas to its proper 

 section. The species destitute of a posterior anal canal are not con- 

 sidered in this arrangement. 



Family RANELLIDiE 

 Genus BURSA Bolten 



Subgenus Bursa s. s. 

 Shell with the spire elevated and surface sculptured. 

 Operculum with lateral nucleus. 



Varices uniformly lateral and continuous. 

 Anal sinus at the suture, short. 



Shell thin, without a continuous callus on the body. 

 Varices spinose. Sect. Bursa (spinosa Lam.). 

 Varices crenate. Sect. Marsupina (spadicea Mtf. or 

 crassa Dillwyn). 

 Anal sinus extended as a gutter on the body. 



Body with a continuous rugose callus with elevated 

 margin. 

 Varices subspinose. Sect. Chasmotlicca (foliata 

 Broderip). 



