I I 76 LAMKI.I.IDENS 



A fine matched pair with the label U. generosus Gould, is in 

 the Lea collection, presented by Dr. Gould from Nevvville, 

 British Burma. It has a rather well-developed post-dorsal 

 wing and shows decided, concentric sculpture. 



Lamellidens canefrianus Simpson. 



Shell somewhat obovate, convex, rather thin, inequilateral ; 

 beaks compressed, their sculpture consisting of delicate, curved, 

 radial ridges, which are subnodulous and inclined to break up 

 into zigzags ; posterior ridge low. rounded ; there are two 

 delicate, pinched-up ridges above on the dorsal slope, which 

 fade out below, anterior end somewhat narrowed, rounded; 

 posterior end bluntly pointed above the median line; dorsal 

 slope obliquely truncate ; dorsal and basal outlines lightly 

 curved, the latter quite full behind the middle ; surface with 

 fine, concentric strise with excessively fine, radial, microscopic 

 lines in front, very faintly granular on the disk ; epidermis 

 brilliant yellowish-green, smoky-tinted green on the dorsal 

 slope ; teeth delicate, compressed ; nacre whitish. 



Length 89, height 44, diam. 27 mm. 



Prome, Lower Burma. 

 Unio protcnsHS Tapperone-Canefri, Am. Mus. Civ. Gen., 



Vn, 1889, p. 349. 

 LaincUidcns caiicfriainis Simpson, Syn., 1900, p. 857. 



I am very doubtful whether this is anything but a variety of 

 marginalis. Several specimens from Fea, of the type lot, are 

 before me, none of them quite grown, but they are all in 

 beautiful condition, and show the character of the beaks and 

 surface perfectly. The shell is shorter in proportion than most 

 marginalis, and is much produced on the post-basal region. 

 The name protensus was used by Lea in 1865 for a North 

 Carolina Unio, hence I have changed it as above. 



Lameleidens jenkinsianus (Benson). 



Shell somewhat solid, subinflated, irregularly long oval ; 

 inequilateral ; beaks full and high ; anterior end subangulate 

 above, rounded below; base line nearlv straight; dorsal, out- 



