NO. 3205. syyopsis OF THE XAIADES SIMPSON. 801 



ridges on the posterior slope; beaks rather low, the sculpture coarse, 

 irregular, broken bars, somewhat doubly looped and swollen on the 

 posterior ridge, with strong, radiating- ridges behind them; pseudocar- 

 dinals solid, often compressed in the direction of the axis of the shell; 

 laterals granular ; beak cavities moderately deep ; one or more granular 

 calluses behind the laterals; nacre white or lurid, slightly radially 

 granular outside the pallial line. 

 Animal unknown. 



tQAUDRULA LEAI Gray. 



- 1 'nio leal GRAY, Griff. Cuvier, XII, 1834, p. 600 (index), pi. xxi, fig. 1. ' * CATLOW 

 ami HEEVE, Couch. Norn., 1845, p. 60. ' BENSON, .11. As. Soc. Calcutta, XXIV, 

 1855, p. 136 (p. 18, reprint). *H. and A. ADAMS, Gen. Rec. Moll., II, 1857, p. 

 496.* KUSTER, Conch. Cab. Unio, 1861, p. 232, pi. LXXVIII, fig. 3.-* ? HEUDE, 

 Conch. Fluv. Nank., 1, 1875, pi. iv, fig. 10, pi. vi. * GREDLEH, Jahrb. Dentsch, 

 Mai. Ges., VIII, 1881, p. 122.* vox MARTENS, Sitzber. Nat. Fr., 1885, p. 77. 

 P.ETEL, Conch. Sam., Ill, 1890, p. 157. 



" Margarita ( Unio) leaii LEA, Syn., 1836, p. 17; 1838, p. 16. 



Maryaron ( Unio) leaii LEA, Syu., 1852, p. 23; 1870, p. 34. 



* Unio leeai HANLEY, Biv. Sheila, 1843. p? 182, pi. xxiu, fig. 55. 



" Utiio nodulosus REEVE, Conch. Icon., XVI, 1864, pi. ix, tig. 32. 



t QUADRULA LEAI var. LELECI Heude. 



* Unio leleci HEUUE, Conch. Fluv. Nauk, I, 1875, pi. iv, fig. 12; v, fig. 14. GRED- 



LER, Jahrb. Deutsch, Mai. Ges., VIII, 1881, p. 122. 

 " Unio richthofeni VON MARTENS, S. B. Nat. Fr. 1875, p. 3 ; Mai. Blatt, XII, 1875, p. 



187; Nov. Conch., IV, 1876, p. 156, pi. cxxxvi, figs. 1-3. >2 *PjSTEL, Conch. 



Sam., Ill, 1890, p. 165. 

 ' Unio Itai var. leleci P.ETEL, Couch. Sam., Ill, 1890, p. 157. 



China; Tonkin; Mekong Kiver. 



QUADRULA OVATA Simpson. 



Unio veatitus var. a HEUDE, Conch. Fluv. Nauk., VIII, 1883, pi. LVIII, fig. 112; LIX, 

 tig. 116. 3 



QUADRULA CAVEATA Heude. ^ 



v Unio caceatus HEUDE, Conch. Fluv. Nauk., Ill, 1877, pi. xxiv, fig. 53. * P.*;TEL, 

 Couch. Sam., Ill, 1890, p. 147. 



Unio contritits HEUDE, Couch. Fluv. Nank., VII, 1881, pi. i.vi, fig. 103. * P.KTEL, 



Conch. Sam., Ill, 1890, p. 148. 



" Unio quadrangulosus HEUDE, Conch. Fluv. Nank., VII, 1881, pi. LVI, fig. 104. 

 " P.ETEL, Couch. Fluv. Nauk., Ill, 1890, p. 164. 



China. 



1 A very brief description is given in the index. 



- Von Martens, in a note at the close of Vol. IV, places his species iu the synonymy 

 of U. leleci Heude. 1 am satisfied that leleci is but a variety of U. leai Gray. 

 :! Heinle's name is preoccupied by Lea for a Unio, I therefore chauge it as above. 



Proc. N. M. vol. xxii 51 



