132 PROCEEDINGS OF THE MALACOLOGICAL SOCIETY. 



More elongate, more compressed, and more coarsely striate than 

 S. sulcatum, which it most resembles. Named after Dr. A. F. Kogers, 

 chief of the Stanford University party who discovered tlie freshwater 

 deposits in the Eocene of Corral Hollow. 



Sph^rium (Amesoda) Catherine, n.sp. PI. YII, Fig. 20. 



Shell small, striate, elongate-arcceform, umbones high, nearly 

 medial, hinge-line rather straight, anterior and posterior margins 

 rounded ; habitat apparently lacustrine. 



Lengtli 5, breadth 3-8, depth of valves 4 mm. 



Eocene : Truckee Lake beds, Nevada, 



Hill near Hawthorne on the Belmont stage-road, Nevada. 



There is some doubt whether this species is really a Spltcerium ; tlie 

 arcteform shape is peculiar. Named after Mrs. Catherine Stevens, of 

 San Diego. 



Sph^riuji (Amesoda) Andersoxianum, n.sp. PI. VI, Fig. 11. 



Shell very large, comparing in size with S. (A.) rivicola of Europe. 

 but proportionally less inflated, less elongate, and trigonal-quadrate 

 rather than trigonal-ovate, striate, beaks high ; habitat apparently 

 lacustrine. 



Length 17'5, breadth 15, depth of valve 4 mm. 



Pliocene : Idaho Lake beds, Idaho and Oregon. 



Badland Hills, one mile east of Sand Hollow, Oregon (type) 

 (R. B. Moran) ; near Baker City, Oregon (F. M. Anderson, per 

 I. B. Sturges) ; Oil City, Idaho (E' L. Ickes). 



Named after Mr. F. M. Anderson, of the California Academy of 

 Science, who lias kindly loaned the writer some interesting material 

 from the Pliocene lake deposits of Eastern Oregon. 



Not subsequently recognized : 

 Spharium Spokani, Baird, 1863. 



Spokane and Kootenai Rivers, British Columbia. 

 SpJmrium Californicum, Clessin, 1878. 

 California. 



Genus Musccliuh, Link. 

 Tellina (sp.), Miiller, 1774 {T. lacustris, Miill.) ; Cijclas (sp.), 

 Draparnaud, 1805 ( C caliculata, Drap. = 2\ lacustris, Miill.); 

 Musculium, Link, 1807 {T. lacustris, Miill.) ; Cah/culina, Clessin, 

 1872 (C. caliculata, Drap. = 2'. lacustris, Miill.); Primella, 

 J. G. Cooper, 1890 (Sph(eriu)n (^Primella) Raymondi, J. G. C. = 

 T. lacustris, Miill.). 

 Type, Tellina lacustris, Miiller. 



Shell of moderate size, averaging 10 mm. in length, fragile, quadrate, 

 quadrate-ovate, or quadrate-trigonal, finely concentrically and radially 

 striate, umbones elevated and usually oaliculate, sub-central or slightly 

 anterior, hinge rudimentary, the teeth minute, cardinals frequently 

 undeveloped or when developed those in right valve not separated 

 above ; habitat lacustrine. 



