1. Lanceolaria grayana Lea. 
Taf. 2. Fig. 1-5. 
Unio grayanus Lea, Tr. Am. Phil. Soc, V, 1834, p. 66, T. 9, fie. 26; Obs., I., 1834, p. 178, 
T. 9, F. 26. — Reeve, Conch. Syst., I., 1841, p. 118, T. 87, fig. 4 — 
Hanley, Test. Moll., 1842, p. 117; Biv. Shells, 1843, p. 177, T. 24, fig. 5. 
— Catlow and Reeve, Conch. Nom., 1845, p. 59. — Küster, Conch. Cab. 
Unio, 1856, p. 167, T.47, fig. 5.—H. and A. Adams, Gen. Rec. Moll. II, 
1857, p, 497. — Chenu, Man., 1859, II, p. 142, fig. 700. — Sowerby, 
Conch. Icon., XVI, 1865, T. 25, fig. 191. — Heude, Conch. Fluv. Nan- 
king., II. 1877, T. 16, fig. 36. — Morlet, Journ. de Conch., 1886, vol. 34, 
p- 267. — Dautzenberg et d’Hamonville, Journ. de Conch., 1887, 
vol. 35, p. 222. — Paetel, Cat. Conch. Samml., III, 1890, p. 154. — 
P. Fischer, Cat. Indo-Chine, 1891, p. 224. — Heude, Journ. de Conch,, 
1901, vol. 49, p. 35. — H. Fischer et Dautzenberg, Cat. Indo-Chine, 
in Mission Pavie, 1904, p. 438; Journ. de Conch., 1905, vol. 53, p. 202. 
Margarita (Unio) grayanus Lea, Syn., 1838, p. 14. 
Margaron (Unio) grayanus Lea, Syn., 1852, p. 21; 1870, p. 32. 
Nodularia grayana Simpson, Syn., 1900, p. 806. 
Unio grayii Griffith, Cuviers Tierreich, engl. Ausg. XII, 1834, T. 21, fig. 3. 
Unio (Nodularia) gracillimus Rolle, Nachr. Bl. d. deutsch. mal. Ges., 1904, Jahrg. 36, 
p- 26, T. 4, fig. b, c. — H. Fischer et Dautzenberg, Journ. de Conch,, 
1905, vol. 53, p. 203. 
Testa lanceolata, transversissima, antice rotundata et postice acutissime angulata, prope 
nates et partem posticam plicata; lateribus planulatis; clivo umboniali subcarinato; valvulis 
tenuibus,; matibus prope marginem anticam locatıs, depressis; epidermide luteola, obsolete radı- 
ata; dentibus cardinalibus in valvula utrague duplicbus et erectis; lateralibus longissimis, 
tenuibus, sub-erectisque; margarita pulchra et üridescente. 
Shell lanceolate, very transverse, very inequilateral, rounded before and very acutely 
angular behind, irregularly folded in the region of the beaks, several larger folds on the 
anterior slope, on the posterior portion the folds are parallel being nearly perpendicular to 
the basal margin, flattened on the sides; umbonial slope elevated into a ridge, green; sub- 
stance of the shell thin; beaks depressed, placed very near to the anterior margin; ligament 
thin, not very long; epidermis finely wrinkled, yellowish with obsolete rays, disposed tobe 
greenish on the posterior part; cardinal teeth double in both valves, compressed and erect; 
lateral teeth very long, thin and nearly straight; anterior ceicatrices distinet; posterior cicatri- 
ces confluent;; dorsal eicatrices situated in the cavity of the beaks; cavity of the beaks very 
small; nacre beautifully pearly and iridescent. Lea. 
Schale langgestreckt, schwertförmig, fest. Vorderteil gerundet, sehr kurz, in kreis- 
förmigem Bogen in den Unterrand übergehend, der in der Jugend ganz glatt, horizontal ver- 
