392 DR. G. 8S. BRADY ON THE OSTRACODA 
above is elongated, subhexagonal, sides nearly parallel but deeply sinuated in the 
middle ; sides gradually tapering to the anterior extremity, which is broad and truncate ; 
posterior extremity very wide, with a wide central mucronate projection. End view 
broadly ovate, height and width nearly equal, outline irregularly waved. ‘The shell- 
surface is sculptured with large pits, which are arranged in obscurely radiating, some- 
what flexuous lines round a central tubercle; parallel to and just within the inferior 
margin is a distinct elevated ridge. Length 3's inch (0°75 millim.). 
This species may perhaps be identical with that called by Egger “ Cythere corrugata, 
Reuss ;” but if so Dr. Egger’s identification must be wrong, as Reuss’s figures certainly 
do not apply to the present species. It was found in the Trophon-antiquum bed (Sables 
supérieurs). 
CyTHERE MACROoPORA, Bosquet. (Plate LXVII. figs. la-ld, and Plate LXVI. 
figs. 6 a-6 d). 
Cythere macropora, Bosquet, Entom. fossil. terr. Tertiair. France, p. 97, pl. v. fig. 2; Jones, Tert. 
Entom. England, p. 35, pl. iii. figs. 9a-9e; Brady, Crosskey, and Robertson, Monog. Post-tert. 
Entom. Scotland, &c., p. 159, pl. xiv. figs. 1-3. 
? Cythere logani, Brady & Crosskey, Geological Magazine, vol. viii. (1871), pl. ii. figs. 8, 9. 
Cythere hornesi, Speyer, op. cit. p. 32, pl. iii. fig. 7, and pl. iv. fig. 1. 
Carapace, as seen from the side, oblong, quadrangular, highest near the front, height 
equal to fully one half the length ; anterior extremity broad and well rounded, posterior 
rounded but narrower; dorsal and ventral margins nearly straight, the former sloping 
rather steeply backwards. The outline as seen from above is oblong and very irregular, 
the margins much jagged and waved; extremities produced, very broad and truncate, 
width about equal to the height. The shell-surface is beautifully sculptured with large 
angular pittings, which are arranged somewhat concentrically round a large rounded 
central tubercle ; the pitted portion of the valve ends at some distance from the hinder 
extremity, in an irregular, curved, abrupt declivity, and is connected with the anterior 
margin by a series of about six short radiating ribs. The anterior margin is fringed 
below the middle with a series of 12-16 short blunt teeth; the posterior margin also 
bears about six or eight distant irregular teeth of similar character. The ventral 
aspect of the shell shows a very broad, prominent central ridge formed by the swollen 
margins of the valves, and on each side a laterally produced expansion ornamented by two 
longitudinal rows of deep subangular excavations. Length 3); inch (1°05 millim. ). 
C. macropora occurs in both beds of “Sables moyens” (abundantly in that of the 
zone & Bryozoaires), and also very abundantly in the Panopwa-bed (‘Sables infé- 
rieurs”). It is certainly one of the most distinctly marked and most beautiful of fossil 
Entomostraca. A recent Australian species (Cythere lactea) described by the present 
writer in 1865 (Trans. Zool. Soc. Lond. vol. v.) comes near to it in character, but is quite 
sufficiently distinct. The form represented in Pl. LX VI. of this Memoir seems to belong 
to the young, and is probably identical with C. hornes?, Speyer. 
