ORDER BRANCHIOPODA. 347 



The Daphnia pulex, the most common of all, f Monoculus 

 pulex, Linn.) ; pulex aqiiaticus arhorescens, Swamm. Bib. 

 Nat. xxxi ; Perroquet cVeau, Geoff. Hist. Ins. ii. p. 455 ; 

 Schoeff. Die. Grlin. arm. polyp. 1755, i. 1. 8.; Straus, Mem, 

 du Mus. d'Hist. V. xxix. 1 — 20 ; Jurine, Mon. viii. — xi. has, 

 according to M. Straus, the beak large and convex ; the setae 

 of the oars plumose ; the first nipple of the sixth segment, in 

 the form of a little tongue ; the valves denticulated at the in- 

 ferior edge, and terminated by a short tail, obtuse in the 

 females. This last character distinguishes it from another 

 species, with which it has been confounded, the D. longispina, 

 Sir. Deg. Insect. VII. xxvii. 1 — 4. 



See for the other species, the afore cited memoir of M. 

 Straus : Muller, Entom, and Jurine Hist, des Monocles, se- 

 cond family, pag. 185. 58. and p. 181 — 200. See also, for 

 D. sinia, and longispina, Ramd. Monoc. v. — vii. 



The last subgenus of the lophyropa is that of 



LynceuSjMm^/. Chilodorus, Leach. 



Which is but little distinguished from the preceding, except 

 by its oars, evidently shorter than the shell, and the lower 

 portion of which makes little or no projection. According to 

 M. Straus, the articulations of their branches should be more 

 numerous than in the preceding subgenera ; all have in front 

 of their eye a small spot, which has the appearance of another 

 eye ; the beak is proportionally more elongated than that of 

 daphnia, curved and pointed. 



See Mull. Entom. G. lynceus. Jurine, Monoc. pag. 

 151—158; and Desmar. Consid. 375—378. 



The second section of branchiopoda, that of Phyllopa, 

 is distinguished, as we have said, from the first, by the num- 

 ber of the feet, which is at least twenty, and by the lamellate 

 or foliaceous form of their articulations ; the eyes are always 



