rsEUjjoDox. 153 



Long. 59, lat. 140, diam. 32 mm. 



Hah. Sahven River, Burma; Tenasserim River {lad. Mus. 

 Coll). 



288. Pseudodon (Pseudodon) iiicobaricus (j\Id)-c7i). 



Pseudodon {Fsciidodou) xicobariciis (Murcli) ; Simpson, Washington, 

 D.C., Smiths. Inst., Nat. Mus. I'roc. xxii, 1900, p. .^:58. 



Alasmodontn (subg. ?) nicohurica. O. Fabiicius ; Murch, J. Conchy liol., 

 Paris, XX, 1872, p. 327. 



Orujinal description : — Testa irregulariter ovalis, convexiiiscula ; 

 striaj iiicremeuti irregulares ; dimidium testcC marginem versus 

 olivaceum, fasciis obscurioribus, radiis numerosioribus, obsoletis, 

 obscure viridibus. lutus argentea, postice iridescens. Umbones 

 plani, erosi, autice siti ; margo dorsalis parum arcuatus, (margo) 

 auticus rotuudatus, angustior, (margo) ventralis antice et postice 

 sat arcuatus, medio leviter inflexus, (margo) post, angustus leviter 

 retlexus. Dentes cardinis tere omniiio evanescentes, dens lat. 

 post, linearis obsoletissinuis. 



Anodoiita zoUinrien, Mousson (Java, p. 9G, t. 18, fig. 1), affinis, 

 sed species Pabricii differt : margiue ventrali areuato, postice 

 subito asceudente, nee nou marguie dorsalis deciivi, baud areuato. 



Hah. Nicobar Islands {0. Fabricius). 



The species was described from a single specimen witliout figure 

 or dimensions being given, it does not seem to have come to light 

 again at any time. 



Section BINEURUS. 



Bineurns, Simpson, AVashiugton, D.C., Smiths. Inst., Nat. Mus. 

 Proc. xxii, 1900, p. 839. 



TsPE, Monocondi/lcea moiJioti, Lea, from Cambodia and Siam. 



liamje. Cambodia ; Siam ; Perak ; Burma. 



Original description : — Shell elongate rhomboid, thin, rounded in 

 front, widely and feebly biangulate beliind, having two or more 

 raised radiating lines on the ])osterior slope, which is somewhat 

 obliquely wrinkled ; beaks low ; surface finely, irregularly, con- 

 centrically grooved ; epidenuis oHve ; teeth smooth, compressed; 

 nacre bluish. 



Animal unknown. 



289. Pseudodon (Bineurus) ava (Theobald). 



Pseudodon (Bineurus) ava (Tlieobakl) ; Simpson, Washington, 

 J).C., Smiths. Inst., Nat. Mus. Proc. xxii, 1900, p. 839. 



MoHocondylaa ava, Theobald, J. A. S. B. xlii, 1873, pt. '2, p. 209, 

 pi. 17, tig. l.j. 



Original description : — Testa oblonga, solidinseula, antice rotun- 

 data, postice curvatim truncata. Margine ventrali recto ; liga- 

 mentali convexo. Umbonibns decorticatis. Epidermide picea in 

 juuioribus luteo-flavescente lineis tenuibus obscure radiatim 



