292 Records of the Indian Museum. [VoL. VII, 
Viz p.' 61) | pl. Sexe fee hGar Obs. sls (p5205 spl soa ooo 
Margaron (Unio) pazti, Lea, Syn., 1870, p. 30. 
China; Reg. No. 524. 
40. Nodularia (Nodularia) olivaria (Lea), Simpson, Syn. 
Naiades, Proc. U.S. Nat. Mus., XXII, p. 817,—Unio olvarius., 
Lea, Tr: Am: PhilSoc¥ IV Spr 108; pl exwik fe 236) Obs. 
p. 118, pl. xvi, fig. 33; Hanley and Theobald, Conch. Ind., p. 5, 
pl. x, fig. 1.=Margarita (Umo) olivarius, Lea, Syn., 1836, p. 26; 
1838, ‘p. 20; 1852, p. 30; 1870, p. 47,—Unio pumtlo, Kuster, 
Conch. Cab, Unio; 1862 p:+208 spl xe dig. 7- 
Assam, Reg. Nos. 2472, 5159; Saharanpur, Reg. Nos. 2445 and 
s221; Kast Cachar (Museum Collec‘or), Reg. No. *295; Moradabad, 
United Provinces (Laidlay), Reg. No. =1s0; North-East Cachar, 
Reg. No. £°°7; Raniganj, Bengal, Reg. No. #182. 
41. Nodularia (Nodularia) theobaldi (Nevill, MS.), sp. n. 
Shell ovately rectangular, very slightly curved, gaping an- 
teriorly, moderately solid, concentrically striate, covered with a 
dark, olivaceous periostracum; umbones small, not prominent ; 
dorsal margin somewhat arched, ventral margin slightly excavated 
in the median region, otherwise straight; anterior side slightly 
produced and scmewhat sharply rounded; posterior side very 
obtusely rostrate, steeply sloping above, then sharply rounded and 
again sloping inwards below. Cardinal teeth in right valve roughly 
triangular, jagged, somewhat inwardly projecting, fitting between 
two teeth in the left valve which are roughened and of which the 
anterior is rather broad and massive; lateral teeth in both valves 
elongate and nearly straight; anterior scars somewhat deeply 
excavated especially above; posterior scars ovate, lightly im- 
pressed; interior of shell nacreous, shading from pale flesh colour 
to bluish iridescent especially towards the posterior margin. 
Long. 34, lat. 60, diam. Ig mm. 
Hab.—Manipur, Assam, Reg. Nos. +719 [Type], 2475. 
42. Nodularia (Nodularia) pecten,sp.n. (PI. viii, figs. 3, 4.) 
Shell elongately ovate, rather thin, covered with a finely 
laminiferous periostracum of a pale bluish green colour shading to 
yellowish green towards the margins, finely concentrically striate 
and posteriorly ribbed, especially on the left valve; umbones 
rather small, moderately prominent; dorsal maigin very slightly 
arched; ventral margin gently curved; anterior side rounded; 
posterior side obtusely rostrate below, sloping above; hinge-teeth 
in both valves weak, anteriorly erect in right valve, sinuous and 
almost twisted in the left; posterior teeth nearly straight, 
moderately elongate; adductor scars scarcely perceptible; interior 
of shell pearly. 
Long. 19, lat. 335, diam. 12 mm. 
Hab.— Pitsanuloke, N. Siam, Reg. No. 596+ [Type]. 
The author follows Simpson in placing this and the next two 
species in the Section Nodularia, though, owing to the very 
