NO. 1203. Sl'SOl'SIS OF THE 5AIAUES VIMI'SOX. 585 



*Cristuria spatiosa VON IHERIXG, Abh. Senck. Nat. Ges., XVIII, 1893, p. 145. 



*Barbala spatiosa P.ETEL, Conch. Sain., Ill, 1J-90, p. 175. 



*Dipaaa plicata var. japonica KOBETT, Abh. Senck. Nat. Ges., XI, 1879, p. 429, pi. 



XLV1I. 



Japan. 



Subgenus PLETHOLOPHUS Simpson, 1900. 

 (Type, Symphynota discoidea Lea.) 



Shell short-elliptical, lenticular, scarcely thickened in front, with 

 compressed beaks which are sculptured with low, wide, concentric 

 ridges, scarcely winged in front or behind, pointed posteriorly; epider- 

 mis smooth, somewhat rayed; hinge teeth very feeble, often nearly 

 wanting; dorsal scars few ; muscle scars faint. Animal unknown. 



tCRISTARIA DI OIDEA Lea. 



*Symphynota discoidea LEA, Tr. Am. Phil. Soc., V, 1834, p. 75, pi. xi, fig. 33 ; * Obs., 



1, 1834, p. 187. pi. xi, fig. 33. 

 *Barbala discoidea H. and A. ADAMS, Gen. Eec. Moll., II, 1857, p. 501. * CHENU, 



Man., 1859, II, p. 145, fig. 716." P.ETEL, Couch. Sam., 1890, p. 175. 

 *Dipsa8 aiscoidea KUSTER, Conch. Cab. Unio, 1862, p. 306, pi. c, fig. 1. 

 * Maryarita ( Unio) discoideus LEA, Syn., 1836, p. 47 ; 1838, p. 28. 

 *Unio discoidem HANLEY, Test. Moll., 1842, p. 214; * Biv. Shells, 1843, p. 214, pi. 



xxi, fig. 57. * CATLOW :md REEVE, Conch. Nom., 1845, p. 58. 

 *Margaron (Unio) discoideus LEA, Syn., 1852, p. 46; 1870, p. 74. 



* Unio tennis GRAY, Griffith's Cuv., XII, 1834, p. 601 (index), pi. xxiv, fig. 2.' 

 *Anodonta cldnensis KUSTER, Conch. Cab. Auo., 1853, p. 51, pi. xn, fig. 3. 

 *UiomagniJicu8 SOWERBY, Conch. Icon., XVI, 1867, pi. LVII, fig. 289. 

 'Anodonta gruneriana CLESSIN, Conch. Cab. Ano., 1875, p. 172, pi. i.vi, figs. 3, 4. 



China. 



CRISTARIA PARVULA Heude.- 



* Dipeas parvulus HEUDE (part), Couch. Fluv. Nank., IV, 1878, pi. xxxn, fig. 65. 

 " Barbala parvula P^ETEL, Couch. Sam., Ill, 1890, p. 175. 



China. 



CRISTARIA REINIANA von Martens. 



*Cristaria reiniana VON MARTENS, Jahrb. Mai. Ges. ,11, 1875, p. 136, pi. in, fig. 4. 



* ? Dipsas reiniana KOBELT, Abh. Senck. Nat. Ges., XI, 1879, p. 432, pi. xn, fig. 4; 



xxi, fig. 2. 



*Anodonta reiniana VON IHERING, Abh. Seuck. Nat. Ges., XVIII, 1893, p. 147. 3 

 *Barbaia reiniana PJSTEL, Conch. Saru., Ill, 1890, p. 175. 



Japan. 



'A brief description is given in the index only. Gray's and Lea's names seem to 

 have been published the same year, and I do not know which appeared first. I use 

 Lea's because it is the one generally known. 



-I am doubtful whether this is more than a varietyof C. discoiden. Heude's figure 

 on plate LIU is a very different thing, which I have called C. radiata. 



3 Martens says it has distinct cardinals and laterals. 



