MUSEUM OF COMPARATIVE ZOOLOGY. 117 



Cerion (Strophiops) glans Kuster. 



A single rather small specimen of this species was obtained by the Fish 

 Commission. 



Macroceramus Gossei Pfeiffer. 



This species is represented by a single young specimen. It is found in 

 South Ftorida, Texas, Cuba, Jamaica, and Curacao. 



Melaniella gracillima Pfeiffer. 



This is also represented by a single specimen. Its range extends to South 

 Florida, Cuba, and St. Thomas. 



Planorbis (Segmentina) dentatus Gould. 



Two specimens apparently of this species (which is by several authors 

 referred to P. albicans Fir., as a synonym) were found by the Fish Com- 

 mission. It was originally described from Cuba, and, if the synonymy referred 

 to is correct, is also a native of St. Thomas, Porto Rico, and Jamaica. One of 

 the specimens was edentate, and might be referred to Adams's variety edentatus. 



Auricula? (Microtralia) minuscula Dall. 



Figure 7. 



This curious little Auriculoid, which mimics the solid Tralia of the shores 

 in form, but is minute and translucent, seems to be not uncommon about the 

 lagoon. It has also been found in South Florida by Mr. Charles T. Simpson, 

 in a similar station. It is probably more nearly related to forms like Auricula 

 pellucens than to Tralia proper, and the sectional name Microtralia is here 

 proposed for it. (Cf. Proc. Dav. Acad. Sci., V. 69, 1889.) 



Sayella Crosseana Dall, var. bahamensis Dall. 



This species, originally described from the low salt marshes of the South 

 Florida coast, is represented by a number of specimens in the Fish Commission 

 collection. The Bahama specimens are somewhat stouter and have more 

 rounded whorls than the Florida shell, and may prove to be distinct. 



Chondropoma Rawsoni Pfeiffer. 



Several specimens apparently belonging to this species, but wanting the 

 operculum, were obtained by the Fish Commission. It was originally de- 

 scribed from Crooked Island, Bahamas. 



