820 PJtOCEEDIXOS OF THE NATIONAL MUSEUM. VOL. MIL 



* Margaron (I'nio) orientalis LEA, Syn , 1852, p. 38; 1870, p. 61. 



* I'nio 2>roductn8 MOUSSON, L. uncl S. W. Moll. Java, 1849, p. 93, pi. xvn, figs. 



3-5; Zeits. fiir Mai., VII, 1851, p. 46. 



" I'nio j>rodi(ctior'L-EA, Syn., 1852, p. 29. * vox MARTKNS, Mai. B1.,XIV, 1866, p. 

 16.* II. and A. ADAMS, Gen. Rec. Moll., II, 1857, p. 494. 



Java. 



Section RADIATTJI.A, Simpson, 

 (Type, I'nin crinpisulcatns Benson.) 



Shell rather solid, triangular oval, with high beaks which are but 

 little inflated, not very full at post base, bluntly pointed behind, the 

 beaks and entire surface covered with radiating, occasionally slightly 

 zigzag or divaricate ridges which are cut more or less into nodules 

 or cancellations by concentric sulcations, the sculpture of the posterior 

 slope stronger, and curving upward; pseudocardinals of the left valve 

 2 to 3, ragged, the anterior larger, two in the right valve, with a 

 parallel sided socket, the larger teeth compressed but rather solid. ' 



fNODULARIA CR1SPISULCATA Benson. 



" I'nio cri8}>isnJcatu8 LEA, Ann. and Mag., X, 1862, p. 193. " SOWERBY, Conch. 

 Icon., XVI, 1866, pi. XLIX, fig. 262. *HAXLEY and THEOBALD, Conch. Ind., 

 1876, p. 6., pi. xi, fig. 5. *P.*;TEL, Conch. Sam., Ill, 1890, p. 149. 



"Margaron (Unio) crispisulcatus LEA, Syn., 1870, p. 31. 



Burma. 



NODULARIA LIMA Simpson. 



* Unio radula BENSON,* in Hanley, Biv. Shells, Snpp., 1856, p. 382. *HANLEY 



and THEOBALD, Conch. Ind., 1876, p. 5, pi. x, fig. 3. * P.ETEL, Couch. Sam., 

 Ill, 1890, p. 165. 

 " Dysnomla radula ROCHEBRUNE, Bull. Soc. Phil., VI, 1882, p. 42. 



Assam; Cambodia. 



Section CJELATURA Conrad. 1853. 

 (Type, Unto teyyptiacus Cailliaud.) 



Shell elliptical, pointed or rounded behind, usually slightly produced 

 at the post base; beak sculpture consisting of zigzag ridges which are 

 generally quite pustulous, the sculpture often extending on to the usu- 

 ally rayed disk; teeth compressed; pseudocardinals lamellar. 



Animal described under Nodularia. (See page 806.) 



(Group of Nodularia cegyptiaca.) 

 Characters the same as of the section. 



'Notwithstanding the considerable difference between this group and all other 

 Nodularias there are species such as occatus, which seem to stand between it and the 

 cccruleus group, and show the relationship of the two. 



2 The name radula was used by Say for a I'nio in 182;>. I change Benson's name as 

 above. I am not positive as to the relationship of this species. 



