44 THE NAUTILUS. 



Pisidium variabilis Prime. Big Black river, Durnnt, Miss. 

 Pisidium noveboracense Prime. Variety, spring, Tuscumbia, Ala. 

 Pisidium peraltum Sterki. Yalabusha river, Grenada, Miss. 

 Pisidium neglectum Sterki. Ms, name ; Black Warrior, Tusca 

 loosa, Ala. 



Pisidium singleyi Sterki. Black Warrior, Tuscaloosa, Ala. 

 Pisidium atlanticum Sterki. Floating creek, Columbus, Miss. 



(To be continued.} 



A NEW SCALA FROM CALIFORNIA. 



BY WILLIAM HEALEY DALL. 



Scala lowei n. sp. 



Shell small, conic, with five or more rapidly increasing whorls 

 after the (lost) nucleus ; color white, whorls very convex with deep 

 sutures and a small, spiral umbilicus ; there is no basal disk or cord ; 

 sculpture of about twenty-seven rather thick, strongly reflected, 

 smooth, close-set varices, and very close, fine, spiral threads, covering 

 the whole whorl between the varices, and separated by about equal 

 sulci ; aperture sub-circular, slightly higher than wide, the reflected 

 margin wide at the outer lip, patulous at the inner base, narrow 

 between the shoulder and the preceding whorl, and at the shoulder 

 produced into a short, rather stout spine which, repeated on successive 

 varices, coronates the whorls. Length of shell (without nucleus), 

 7.0; max. diameter, 4.0 ; max. diameter of aperture, 2.5 mm. 



Habitat: dredged off Avalon, Catalina Island, Gala., in 40-60 

 fathoms, by H. N. Lowe, in 1903. 



This species recalls S. bellastriata Carpenter, in general character, 

 but is smaller ; has more numerous, close-set and more strongly re- 

 flected varices ; and has the spiral striation and threading much 

 finer than in bellastriata of equal size. 



The first shell belonging to Mr. Lowe was returned to him after 

 a figure had been drawn from the specimen. A second specimen was 

 sent by him, from the same vicinity, in 1906, which is retained in 

 the National Museum, No. 191548. This also has lost its nucleus. 

 The six remaining whorls measure 7.0 mm. in length. 



