LAMELUDENS 1 1 69 



Unio marginalis var. cylindrica HanlEy and Theobald, Conch. 



Ind., 1876, p. 20, pi. XEiv, fig. I. 

 Lamellidcns marginaUs var. cylindricus Simpson, Syn., 1900, 



P- 855- 

 Var. hanleyi vSimpson. 



Shell long rhomboidal ; beaks elevated ; posterior ridge ele- 

 vated, rounded; epidermis brownish with a yellowish border. 

 This may possibly be a distinct species. The beaks appear to 

 be more elevated than they are in any other of the forms. 

 Hanley and Theobald believed it to be the Unio corrianus of 

 Lea, but it is not that species at all. 

 Unio marginaUs var. corriana Hanley and Theobald, Conch. 



Ind., 1876, p. 20, pi. XLiv, fig. 4- 

 Lamellidens marginaUs var. hanleyi Simpson, Syn., 1900, p. 



855- 

 Var. exanthematiciis (Kuster). 



This seems to be a small form with a bright yellow epidermis 

 and may be merely a young specimen. 

 Unio exanthematicus Kuster, Conch. Cab. Unio, 1861, p. 243, 



pi. LXXXI, fig. 2. 



Lamellidcns exanthemaUcus Simpson, Syn., 1900, p. 856. 

 Pressidens exanthematicus Haas, Conch. Cab., Unio, 1912, pi. 

 23, figs. 6-9^. 



Var. sublamellatns Preston. 



"An elongate, somewhat rostrate form, having the hinge 

 teeth rather less developed." (Preston). 



Type locality, Burma. 

 Lamellidcns marginalis var. sublamellatns PrEston, Rec. Ind. 



xMus., VII, 191 2, p. 305. 



Var. sazvaddycnsis Preston. 



"Shell much more ovate and convex than the typical form, 

 having the dorsal margin more arched and posteriorly ascend- 

 ing, the ventral margin and anterior side more rounded, and 

 the posterior side produced and roundedly rosrate." (Preston). 



