5Q THE NAUTILUS. 



being found in Margaritana arcuata. I have a friend who has done 

 quite a business in collecting them from that mussel." 



E. H. Harn, Blairsville, Pa. in five years, has found 64 species 

 and varieties of shells in his neighborhood. That is a sample of 

 what can be done by patient search. 



Mrs. M. Burton, Williamson University, Cal. sends us a copy of 

 the Weekly Tribune of Los Angeles, Cal. of August 16th, contain- 

 ing an interesting article'by Virginia Burton, upon the " Coffee-bean 

 Cowries" of the California Coast (Trivia Solandri and Trivia Cali- 

 fornica.) 



Mr. Frank C. Baker, who has been studying at the Academy of 

 Natural Sciences of Philadelphia for a year past, and who was one 

 of the members of the expedition sent by the Academy to Southern 

 Mexico, has accepted a position with Prof. Henry Ward of Roch- 

 ester, New York, in his department of Invertebrates. Mr. Baker 

 leaves many warm friends in Philadelphia, where he will be missed 

 from the circle of conchologists as well for his kindly personal 

 qualities as for his recognized ability in the study of Mollusks. 



THE SHELL-BEARING MOLLUSCA OF RHODE ISLAND. 



BY HORACE F. CARPENTER. 



FAMILY UNIONIDiE. 



Genus Anodonta, Cuvier. 



Shell transversely elongated, inequilateral, thin, toothless. 



To distinguish instantly between the three genera, Unio, Mar- 

 garitana and Anodonta, it is only necessary to examine the hinge. 

 Unio has cardinal and lateral teeth in each valve ; Margaritana has 

 cardinal teeth, but no laterals, while Anodonta has no teeth, the 

 valves being held together only by the ligament. 



There are two hundred species of Anodonta, distributed world 

 wide. Two of these are known to inhabit R. I., and a third may 

 possibly be found within its limits. 



193. — Anodonta cataracta, Say. 

 Syns. : 



Anodonta fluviatilis, Lea, Gould, Stimp. 



MytUlus illictus, Solander. 



Shell thin, inflated, transversely sub-oval, fragile ; basal margin 

 curved ; hinge margin straight ; epidermis smooth, excepting at the 



