NO. 1205. SYKOPSrs OF THE NAIADES— SIMPSON. 867 



lateral in the right valve and two in the left, which show traces of 

 vertical striation; beak cavities deei^, not compressed; nacre purple.^ 

 Animal unknown. 



fCASTALIELLA SULCATA Krauss. 



^Castalia sulcata Krauss, Zeits. fiir Mai., 1849, p. 99. — * P/Etel, Couch. Sam., Ill, 

 1890, p. 190. 



* Unio kraussii Lea, Pr. Ac. N. Sci. Phila., VI, 1853. p. 376.^ 

 *Margaron ( Unio) kraunsii Lea, Syn., 1870, p. 35. 



Surinam. 



Genus CALLONAIA Simpson, 1900. 

 (Type, Castalia duprei Recluz.) 



Shell triangular, thin, inflated, with very high, full beaks which 

 appear to be without sculpture;^ a very high, sharp posterior ridge 

 extends to the base of the shell, above which it is decidedly truncated; 

 anterior end somewhat pointed above, rounded below; ligament very 

 short; surface nearly smooth but somewhat sulcate anteriorly; epi- 

 dermis bright greenish yellow, shining; hinge line strongly arched; 

 teeth compressed, high ; two pseudocardinals in each valve, all inter- 

 locking and side by side; one lateral in the right valve and two in the 

 left, a little ragged and granularly vertically striate; beak cavities very 

 deep, not compressed; muscle scars superficial; nacre brilliant, bluish 

 white, radiately striate posteriorly. Animal unknown. 



t CALLONAIA DUPREI Recluz. 



* Castalia duprei Eecluz, Rev. Zool., 1843, p. 305, pi. xxxv; *Mag. Zool., 1843, 



p. 1. — *H. and A. Adams, Geu. Rec. Moll., II, 1857, p. 509. — * Chenu. Man., 

 1859, II, p. 149, fig. 738.— *PyETEL, Conch. Sam., Ill, 1890, p. 189. 



* Unio duprei Catlow and. Reeve, Couch. Nom., 1845, p. 58. 



"" Margaron (Prisodon) duprei Lea, Syn., 1852, p. 18; 1870, p. 27. 

 ""Castalia dolabella Sowerby, Conch. Icon., XVII, 1869, pi. iii, figs. 13 a, 13 1), 13 c. — 

 * P.ffiTEL, Conch. Sam., Ill, 1890, p. 189. 



Great lakes of Para, Brazil. 



'This species, of which the type is in the Lea collection, has some of the characters 

 of Prisodon and Castalina, but I can not satisfactorily refer it to either, and it is cer- 

 tainly not a,Diplodon. Its strong sulcation, reddish chestnut epidermis, and purple 

 nacre are characters that are not possessed by any South American Naiades that I am 

 acquainted with. 



^Lea received this shell from Dr. Dunker under the name of Castalia sulcata Krauss. 

 Believing it to be a Unio, he placed it in that genus, and the name sulcatus being 

 preoccupied in Unio, he changed it as above. 



^In oue of Lea's shells the beaks are almost perfect, and not a sign of sculpture 

 can be seen. 



