ORDER BRANCHIOPODA. 349 



situated underneath, consisting of two mandibles, swelled, 

 arched, and truncated at their lower extremity, and of two 

 foliaceous jaws. These parts form, when united, a sort of 

 inferior beak. The body, properly so called, is divided intq 

 twenty-three segments, each supporting, with the exception 

 of the last, a pair of branchial feet. All these feet are similar, 

 very much compressed, bifid, with the external division simple, 

 ciliate at the external edge, and the other quadriarticulate, 

 and strongly ciliated at the internal edge. The first twelve 

 pairs are of the same length, and larger than the others. 

 The length of the latter diminishes progressively. The eleventh 

 pair, and the two following, have at their base a slender fila- 

 ment, ascending into the cavity, which is between the back 

 and the testa, and serving as a support for the eggs. The last 

 segment, or tail, is terminated by two filaments. The ovaries 

 are interior, and situated on the sides of the alimentary canal, 

 from the base of the first pair of feet as far as the eighteenth, 

 and their issue appears to be situated at the root of some of 

 them. The eggs, after the laying, occupy the dorsal cavity, 

 of w'hich we have spoken, and are attached there, by means 

 of small filaments, themselves adhering to those of the sup- 

 ports. They are at first round and transparent; they then 

 assume a yellowish tint, which afterwards grows obscure at 

 the centre, and their figure becomes irregular and angular. 



All the individuals observed by M. Adolphe Brongniart, 

 were provided with them. The males, supposing any to exist, 

 do not appear at the same time as the females, that is, in 

 the month of June, and are unknown. 



Limnadia Hermani, Adol. Brong. Mem. du Mus. d'Hist. 

 Natur. VI. xiii. ; Daphnia gigas. Herm. Mem. Apterol, v., 

 has been found in great numbers, in the small pools of the 

 forest of Fontainbleau. 



In other cases, each eye is situated at the extremity of a 

 pedicle, formed by the lateral and horn-like elongation of each 



