112 THE NAUTILUS. 



umbilical region somewhat calloused, the place of the umbilicus 

 marked by a moderately sunken pit, surrounded by n weak spiral 

 rib which terminates in a faint denticle at the junction of the colu- 

 mellar and basal margins of the peristome. Alt. 14, diam. 1G^ mm. 



Beagle Channel, Patagonia (Dr. H. von Ihering). 



This species (No. 1020 of von Ihering's register) is obviously 

 unlike the forms of eastern Patagonia, and there is nothing like it in 

 Mabille and Rochebrune's work on Cape Horn mollusks. Of the 

 Chilian species, it is allied only to O. fusccscens Phil.,* but in C. 

 Orbi gnyamun the whorls are more convex, the prevailing color black, 

 and it is imperforate. 



ON A COLLECTION OF FRESH-WATER SHELLS FROM RHODE ISLAND. 



BY FRANK C. BAKER. 



During the month of July, 1899, the writer made a collection of 

 marine and fresh-water shells in the state of Rhode Island, and a list 

 of the fresh-water species may be of interest. Collections were made 

 at the following places : 



1. Nayatt, R. I. A small pond between the railroad depot and 

 the bay. The bottom is made up of soft, black, carbonaceous mud, 

 and the shores are lined with dead leaves and twigs. 



2. Newport, R. I. Bailey's Pond, near Bailey's Beach. A pond 

 of good size and considerable depth, bordered by cat-tails. 



3. Providence, R. I. Cat Swamp. A small clear stream, flowing 

 through a flag-swamp. The numbers after the species indicate the 

 above localities. 



Calycidlna partumeia Say. 1, 2. Common. 



Calyculina truncata Linsley. 1. Common. 



Calycidlna securis Prime. 2. Not common. 



Pisidium, near abditum, but possibly P. lens Sterki. 1. Common. 



Pisidium splendidnlum Sterki. 1,2. Not common. 



Limncea palustris Miiller. 3. Common. 



Planorbis tricohis Say. 2, 3. Common. 



Plonorbis deflectm Say. 1. Common. 



Planorbis parvus Say. 1,2,3. Common. 



*Conchylien Cabinet, Trochus, p. 182 ; Man. of Conch., XI., Trochidx, p. 181. 



