1909.] NATURAL SCIENCES OF PHILADELPHIA. 539 



found the small species taken in this stream. They were in the sedi- 

 ment, and on water plants and near the water's edge. The stream is 

 clear, deep and with a strong current. 



This may turn out to be a small, rayed variety of L. novileonis, yet 

 specimens from 28 to 36 mm. long have every appearance of adult 

 shells. The cardinal teeth in the left valve are stouter and their crests 

 are more united than in L. novileonis. 



While L. undivaga, coyensis and novileonis are closely related species, 

 they seem, with present material, to be distinct. 

 Lampsilis metallica ganina "- subsp. PI. XXVII, fig. 0. 



The shell resembles L. metallica (Say) (Unio cuprinus Lea) in 

 general appearance, but is constantly smaller, more compressed and 

 more reniform. Near the beaks there are green rays on a pale ground, 

 the rest of the valve being brownish black. 



Length 47, alt. 25, diam. 13^ mm. 

 47^, " 264, " is" " 

 39, " 21, " 13 " 



Ganina River, three miles southwest of San Dieguito. The speci- 

 mens are heavily incrusted with calcareous matter posteriorly, but are 

 free from erosion. 



Glabaris strebeli (Lea). PI. XXVII. fig. S. 



Anodonta strebeli Lea, Obs., XII, p. 82, pi. 52, fig. 135 (Vera Cruz). 



Tampamolon Creek, two specimens. Casas Viejas River, one 

 young shell. 



The epidermis is very glossy anteriorly, but dull and shortly lamellose 

 on the posterior half. In the median part there are several rays 

 composed of short threads in the direction of growth-lines, but caught 

 up and interrupted in the middle, as though scored upward when soft. 

 These peculiar markings occur on some other species of Glabaris, and 

 are constant in all the specimens of G. strebeli I have seen from Vera 

 Cruz and San Luis Potosi. The anterior end of the shell has a sculpture 

 of threads along the lines of growth. The sinulus, or glossy area at 

 the posterior end of the hinge-line, is triangular, pointed below, as in 

 Glabaris. not shallow, as in Anodonta; so that Mr. Simpson's reference 

 of the species to Glabaris is justified. It ranges north farther than 

 any other species of the genus. G. cylindraccus (Lea), from the 

 Medellin River, is evidently an allied form. 



