no. 1642. NEW SHELLS FROM MEXICO— DALL. Igl 



LAMPSILIS (PROPTERA) SALINASENSIS Simpson, new species. 

 Plate XXX, fig. 3. 



Shell somewhat obovate, subcompressed or convex, inequilateral, 

 moderately solid; beaks small, nearly or quite smooth, pointed and 

 turned forward over a small lunule, subcompressed; posterior ridge 

 rounded, ending in a blunt point below the median line of the shell; 

 anterior end narrowed, rounded, basal and dorsal outlines lightly 

 curved; surface with irregular growth lines, and traces of micro- 

 scopic radial sculpture; dorsal slope feebly nodulouslv sculptured; 

 epidermis yellowish green with feeble wide or narrow greenish rays 

 and a yellowish band near the border; pseudocardinals subcom- 

 pressed, ragged, two in each valve; laterals remote, delicate, double 

 in the left valve, single in the right, much elevated behind; muscle 

 scars rather shallow; nacre blue, with a wide prismatic border. 

 Length, 70 mm. ; height, 40 mm. ; diameter, 20 mm. 



Salinas River, Coahuila, Mexico, Nelson and Goldman; also from 

 Valles River, Valles, Mexico, A. A. Hinkley. 



The types are Cat. No. 163156, U.S.N.M. 



Three shells were collected, all of which are probably young. It 

 is quite likely that adult shells will prove to be brown. The species 

 seems nearest to L. explicata Morelet, several fine specimens of which 

 are in the National Museum collection. It is obovate instead of true 

 rhomboid, as is that species, and has more compressed and sharper 

 beaks. The posterior slope of L. explicata is nearly or quite smooth, 

 while in the present species it is corrugated. Our specimens are 

 probabl}' all females. 



DIPLODON WEBSTERI Simpson. 



Plate XXX, figs. 1, 2. 

 Diplodon websteri Simpson, Nautilus, XVI, No. 3, p. 30, July, 1902. 



Collected by Rev. W. H. Webster, of Wauiku, New Zealand. Cat. 

 No. 162342, U.S.N.M. 



A figure of this species, of which the type is in the U. S. National 

 Museum, has been frequently called for, and the present opportunity 

 was thought suitable, the drawing by the late Dr. J. C. McConnell 

 having been in hand a long time. 



