NO. 1205. SYNOPSIS OF THE NAIADES— SIMPSON. 533 



fLAMPSILIS DOLIARIS Lea. 



Unio doUaris Lea, Pr. Ac. N. Sci. Phila., XVII, 186.5, p. 88; *.J1. Ac. N. Sci. Phila., 

 VI, 1868, p.260, pi. xxxii, tig. 75; "Obs., XII, 1869, p. 20, pi. xxxii, fig. 75.— 



* B. H. Wright, Check List, 1888. 



* Margaron ( Unio) doUaris Lea, Syn., 1870, p. 42. 



Alabama and Tombigbee drainage. 



fLAMPSILIS BREVICULUS Call. 



* Unio irevioulus Call, Pr. U.S.Nat. Miis., X, 1887, p. 499, pi. xxviii; * Tr. Ac. 



Sci. St. Louis, VII, 1895, p. 6, pi. xvii. 



tLAMPSILIS BREVICULUS var. BRITTSI Simpson. 

 *Lampsilis irittsi Simpson, Pr. Ac. N. Sci. Phila., 1900, p. 76, pi. v, figs. 1, 2.' 

 White and Current rivers, Arkansas; Texas County, Missouri. 



tLAMPSILIS BIANGULATUS Lea.- 



* Unio Uangulatus Lea, Pr. Am. Phil. Soc, 1, 1840, p. 288 ; * Tr. Am. Phil. Soc, VIII, 



1843, p. 197, pi. IX, fig. 8; * Obs., Ill, 1842, p. 35, pi. ix, fig. 8.—* Conrad, Pr. 

 Ac. N. Sci. Phila., 1853, p. 245.— *Chenu, 111. Conch., 1858, pi. xxx, figs. 

 7, la, 76.— *H. and A. Adams, Gen. Rec, Moll., IL 1857, p. 492.— *Kuster, 

 Conch. Cab. Unio, 1861, p. 189, pi. LX, fig. 1; pi. lxi, fig. 1. — *Sowerby, 

 Conch. Icon., XVI, 1868, pi. Lxxx, fig. 421.—* B. H. Wright, Check List, 

 1888.—* P^TEL, Conch. Sam., Ill, 1890, p. 146. 

 Margaron ( Unio) hiangidatus Lea Syn., 1852, p. 38, 1870, p. 61. 



Tennessee drainage. 



LAMPSILIS SUBVEXA Conrad.3 



*Anodonta subvexa Conrad, Am. Jl. Sci., XXV, 1834, p. 341, pi. i, fig. 1 ; *New F.W. 

 Shells, 1834, p. 73. — * Ferussac, Guer. Mag. 1835, p. 25.— *Moller, Syn. Nov. 

 Gen., 1836, p. 194.— * Conrad, Pr. Acad. N. Sci. Phila., VI, 1853, p. 264.— 



* H. and A. Adams, Gen. Eec. Moll., II, 1857, p. 503.— *B. H. Wright, Check 

 List, 1888.—* P.etel, Conch. Sam., Ill, 1890, p. 185. 



'At the time I published the L. hrittsi I believed it to be a valid species. Since 

 then I have seen additional material which seems to be a connecting link between 

 it and L. bi-einciihis. I can not be certain as to the relationships of this form, which 

 seems on the one hand to have characters belonging to the typical section oi lamp- 

 silis and on the other to be related to L. spatiilatiis and L. pleasi. 



2The systematic position of this species is a little uncertain. In the form of the 

 shell and the teeth it seems to belong in the Ventricosns grouj), but the texture and 

 broken rays apparently ally it to the LigamenUnun group. The soft parts agree best 

 with those of members of the former assemblage, so I place it here. 



^I do not know what this is, nor where it belongs, but it is certainly not a true 

 Jnodonta. The shell, according to Conrad's figure, is rayed throughout, and looks 

 very much like a young U. rentricosus. He says that it has a callus resembling an 

 incipient tooth; that it inhabits the Black Warrior Eiver, and that it is very rare. 

 It is just possible that it is related to some of the so-called Margaritanas of the 

 Southern States, such as .1/. spiUmani, but I think it more likely some young form of 

 the f'ciilricosiix group in wliicli the hinge has lieen injured. I place it here with the 

 greatest hesitation. 



