90 
extremity, beaks, and dorsal edge of a purplish tint possessing a 
somewhat metallic lustre ; the interior is of a light purple tint and 
somewhat shining lustre; the ribs are numerous, about 34 in num- 
ber, and prominent, and the surface between them is striated longi- 
tudinally and impressly punctate, the strize extending across one-half 
the space, the other half being occupied with the punctations. 
Hab. India, Capt. Boys. Brit. Mus. 
Sp. 8. Esruerra stmiis, Nobis. (Pl. XI. f. 7, 7a, 76, 7¢.) 
Carapace-valves elongate obovate ; anterior extremity considerably 
broader than posterior, which is rather narrow; beaks very promi- 
nent, placed very near anterior extremity ; carapace opake ; colour 
externally and internally the same as in last; the ribs are numerous 
and prominent, the first 7 or 8 rather broader than the rest, smooth, 
and flattish ; the remainder sharply prominent, and having on their 
surface a row of sharp angular beads; the surface between the ribs 
is deeply striated, the striee extending nearly quite across the space. 
This species differs from the preceding in being smaller, more elon- 
gate in proportion; in having the posterior extremity considerably 
narrower and sharper, and the beaks nearer anterior extremity, and 
in having the ribs beaded. 
Hab. India, Capt. Boys. Brit. Mus. 
Sp. 9. EstHERIA TETRACERA. 
Syn. Limnadia tetracera, Krynicki, Bull. Soc. Imp. Nat. Mos- 
cou, 1830, 176. t. 7. f. 1, 2. M. Edwards, Hist. Nat. Crust. i. 
363. No. 3. 
Tsaura tetracera, Joly, Aun. Se. Nat. 2nd ser. xviii. 
Carapace-valves broadly obovate ; anterior extremity broader than 
posterior, which is obtusely rounded; beaks prominent, very near 
anterior extremity. 
Not having seen this species I cannot describe the structure of the 
carapace. 
Krynicki describes this species as a Limnadia, but at the same 
time remarks “that it ought to form the type of a new genus.” 
Hab. Neighbourhood of Charkow, Russia, Krynicki. 
June 12, 1849. 
W. Spence, Esq., F.R.S., in the Chair. 
The Secretary reported that the youngest female Bison had given 
birth to a calf im the Menagerie on the 6th inst. after an apparent 
gestation of 270 days. A fine male example of Macropus major had 
been added to the collection by purchase. 
