586 PEOCEEDINaS OF THE NATIONAL MUSEUM. 



CRISTARIA GENTILIANA Heude. 



■'^Cristaria (jeniilianus Heube, Conch. Fluv. Nank., VII, 1881, pi. Liii, fig. 98. 

 "Barbala gentiliana P^tel, Conch. Sam., Ill, 1890, p. 175. 



China. 



t CRISTARIA SWINHOEI H.Adams. 



* Unio sivinhoei H.Adams, Proc. Zool. Soc. Lond., 1866, p. 319.'— Sowerby, Conch. 



Icon , XVI, 1868, pi. xlii, fig. 232.— P^tei., Conch. Sam., Ill, 1890, p. 169. 

 ^ Anodonta swinhoei H. Adams, Proc. Zool. Soc. Lond., 1866, p. 446.— " Clessin, 

 Conch. Cab. Anodonta, 1876, p. 125, pi. lxxv, fig. 6.— * PiETEL, Conch. 

 Sam., Ill, 1890, p. 185. 



* Anodon swinhoei Sowerby, Conch. Icon., XVI, 1868, pi. xxvii, fig. 108. 

 "^ Margaron ( Unio) swinhoei Lea, Syn., 1870, p. 45. 



Formosa; Tonkin; Cambodia. 



Subgenus CEASSITESTA Simpson, 1900. 



(Type, Cristaria radiata Simpson.) 



Shell rather solid, elliptic-rhomboid, with a rounded posterior ridge, 

 scarcely winged; beaks full, sculpture not seen; epidermis bright, 

 strongly rayed, with two conspicuous light and three dark rays on the 

 posterior slope; hinge line curved; pseudocardinals and laterals 

 led need to the merest vestiges; dorsal scars only one or two in the 

 cavity of the beaks; adductor scars faint; nacre lurid. 



t CRISTARIA RADIATA Simpson.^ 



"* Dipsas partnilus Heude (part). Conch. Flnv. Nank., VII, 1881, pi. lii, fig. 96. 



China. 



Genus LEPIDODESMA Simpson, 1896. 



(Type, Unto langiiilafi Heude.) 



Lejndodesma Simpson, Proc. U. S. Nat. Mns., 1896, p. 311. 



Shell large, thin, inflated, with a high, sharp, posterior ridge and a 

 second fainter one above, making the hinder part widely biangulate; 

 beaks very high and full, their sculpture, which extends over the whole 

 shell, consisting of ridges that follow the growth lines; there are two 

 rows of radiating nodules, one on the middle of the disk, and a stronger 

 one on the post ridge; ligament very large, wide, covered with con- 

 centric scales; hinge line arched ; two pseudocardinals in the left valve, 

 the anterior elongated, running inwardly across the hinge plate, and 

 ending abruptly, with a shorter, fainter one behind it; with two strong- 

 laterals, the inner the higher, its edge reflexed upward, and suddenly 

 truncate behind; one low elongated pseudocardinal in the right valve, 



1 This seems to be a Cristaria of the discoidea section. The cardinals are somewhat 

 better developed than is common among Cristarias, but are still quite faint. 



-Heude has figured two different species under the name of D'lpsas parcidus, on 

 plate xxxii. I have therefore given the last-described form the name radiata. 



