Sterki: North American Sph,eriid.«. 467 



III. Pisidium ferrugineum Prime. 



Pisidiutn ferruginenni Prime, Boston Proc, IV, 1851, p. 162. 



Habitat. — New England and eastern New York, common. 



1X2. Pisidium rowelli Sterki. 

 Pisidium rowelli Sterki, Nautilus, XVII, 1903, p. 80. 

 Habitat. — California. 



113. Pisidium huachucanum Pilsbry «S: Ferriss. 



Pisidium abditiim huachucanum Pilsbry & Ferriss, Proc. Acad. Nat. Sci. Philada., 

 1906, p. 173. 



Appears to be distinct from P. abdituni. 

 Habitat. — Arizona, Nevada. 



114. Pisidium occidentale Newcomb. 



Pisidium occidentale Newcomb, Proc. Acad. Nat. Sci. Calif., II, 1863, p. 94. 

 Habitat. — California, south to San Diego. 



115. Pisidium insigne Gabb. 



Pisidium, insigne Gabb, Amer. Journ. ConchoL, IV, 1868, p. 69, PI. II, fig. 2. 



The specimens in the Collection of the Academy of Natural Sciences 

 in Philadelphia (No. 58,155) are evidently immature, but appear to 

 represent a distinct species. 



Habitat. — California. 



116. Pisidium ashmuni Sterki. 



Pisidium aihmuni Sterki, Natitilus, XVII, 1903, p. 42. 

 Habitat. — New Mexico, southern California. 



117. Pisidium nevadense Sterki. 



Pisidium nevadense Sterki, Nautilus, XXVI, 1913, p. 137. 

 //a&/7a/.— Nevada County, California. 



118. Pisidium nevadense modicum Sterki. 



Pisidium nevadense var. modicuin Sterki, I. c. 

 Habitat. — White Pine, Nevada. 



119. Pisidium ultramontanum Prime. 



Pisidium ultramontanum Prime, Mon. Corb., 1865, p. 75. 

 Habitat. — British Columbia to California. 



