i 4 EARLY TERTIARY OSTRACODA 



postjacent socket, posteromedian locellate groove and a pessular posterior tooth ; 

 left valve with anterior socket, anteromedian sub-conical tooth, postero-median 

 denticulate bar and a deep posterior socket. 



Comparison. This genus differs from Echinocythereis in having a short vertical 

 ridge below and a furrow behind the eye-tubercle, also there are two frontal scars in 

 Echinocythereis, but only one in Alocopocythere. Stigmatocythere has a curved ridge 

 joining the eye-tubercle and the sub-central tubercle, whereas in Alocopocythere a 

 short, almost vertical ridge joins the eye-tubercle and is delimited posteriorly by a 

 furrow. Henryhowella has three longitudinal plications in the posterior half of the 

 valve and an anterior vestibule, not present in Alocopocythere. Moreover, the 

 frontal scar in Henryhowella is V-shaped, while Alocopocythere has an oval frontal 

 scar. 



Remarks. In addition to the species described here, the Miocene species Trachy- 

 leberis fossularis Lubimova and Guha (i960, p. 40, pi. 3, fig. 7), which Guha in 1961 

 (p. 4, figs. 5, 9) transferred to the genus Echinocythereis should be ascribed to Alo- 

 copocythere. 



Alocopocythere transcendens sp. nov. 

 (Plate 1, figs. 4, 5, 8, 9 ; Plate 2, figs. 1-4, 6, 7) 



Derivation of name. Latin, transcendens, rising above ; with reference to the 

 stratigraphic position in relation to A . abstracta. 



Diagnosis. Strongly reticulate Alocopocythere with rounded postero-ventral 

 margin, sub-central tubercle more or less distinct, eye-tubercle distinct, marginal 

 rim well marked. 



Holotype. Io. 4315, a female left valve (PI. 2, figs. 1, 6). 



Paratypes. Io. 4261 + Io. 3104-6. 



Material. 263 specimens from the Zao River section from 7 horizons (sample 

 nos. 24127, 24131, 24132, 24145, 24147, 24148 and 24151). Approximately 600 

 specimens from the Rakhi Nala section from 46 horizons (sample nos. 3168, 3198, 

 to 3200, 3401 to 3405, 3407, 3409, 3410, 3418, to 3422, 3424, 3426, 3428, 3429, 3432, 

 3434. 3435. 3438, 3457 to 3459. 349$, 3499. 3607, 3614, 3615. 3617 and 3618). GSP. 

 BM. 2508. 



Type locality. Zao River section. 



Type horizon. Upper Chocolate Clays, sample no. 24148. 



Description. Carapace sub-rectangular to sub-quadrate in lateral outline. 

 Sexual dimorphism rather marked, the females being shorter, higher and wider than 

 the males. Dorsal margin sinuous with protruding anterior and posterior cardinal 

 angles, ventral margin almost straight in the right valve but evenly curved in the 

 left valve. Anterior margin broadly rounded, postero-dorsal margin very slightly 

 concave particularly in the right valve, posterior extremity rounded, postero- 

 ventral margin rounded. Valves almost equal in size. Eye-tubercle distinct, rounded 

 and polished. Sub-central tubercle more or less distinct. Shell surface strongly 



