﻿LAMPSILIS 173 



ed, with a few pits under the hinder pseudocardinal, muscle 

 scars superficial, the hinder large ; nacre purple, iridescent, and 

 thinner behind. The male and female shells are very much 

 alike and they end in a faint, wide biangulation a short dis- 

 tance above the base. 



Length 80, height 60, diam. 28 mm. 



Another, length 120, height 76, diam. 50 mm. 



Northeastern Mexico ; southeastern Texas ; Honduras. 

 Unio tampicoensis Lea, Tr. Am. Phil. Soc, VL 1838, p. 24, 



pi. VII, fig. 18; Obs., n, 1838, p. 24. pi. VII, fig. 18. — Chenu, 



111. Conch., 1858, pi. XXI, figs. 5, 5a, 5&. — PKuster, Conch. 



Cab. Unio., 1862, p. 275, pi. xciii, fig. i. — ^PSowerby, Conch. 



Icon., XVI, 1867, pi. Lvii, fig. 291. — VON Martens, Biol. 



Cent. Amer., Moll., 1900, p. 511, pi. xxiii, figs, i, la, ib. 

 Margarita (Unio) tampicoensis Lea, Syn., 1836, p. 22 ; 1838, 



p. 18. 

 Margaron (Unio) tampicoensis Lea, Syn., 1852, p. 26; 1870. 



p. 41. 

 Lampsilis tampecoensis Simpson, Syn., 1900. p. 570. 

 Unio heermannii Lea, Pr. Ac. N. Sci. Phila., XIII, 1861, p. 



392 ; Jl. Ac. N. Sci. Phila., V, 1862, p. 194, pi. xxvi, fig. 263 ; 



Obs., IX, 1863, p. 16, pi. XXVI, fig. 263. — ? SowERBY, Couch. 



Icon., XVI, 1868, pi. Lxxxiii, fig. 441. 

 Margaron (Unio) heermannii Lea, Syn., 1870, p. 28. 



Close to herlandierii but less inflated and solid, with lower 

 beaks, generally darker within and without. But there are in- 

 termediate shells that are hard to place. It attains larger di- 

 mensions than those given above. The female shell of tayn- 

 picoensis is a little fuller behind the center of the base than 

 the male is. 



Lampsilis tecomatensis (Lea)*. 



Shell elliptical, somewhat inflated, solid, with moderate, 

 faintly biangulate posterior ridges, with full, rather high beaks, 

 whose sculpture is not known; epidermis thick, blackish, 

 smooth and shining on the middle of the disk, a little rough- 

 ened around the border and especially on the posterior slope, 



