CRUSTACEA. 641 



Sp. Polyphemus oculus MDELL., (Polyphemus pediculus L. ? ) DE GEEK Mem. 

 s. L Ins. vii. PI. 28, figs. 9, 10, MUELL. Entom. Tab. xx. figs. 15, 

 DESMAE. Crust. PI. 54, figs, i, 2, KOCH, HERRICH-SCHJSFFER Deutschl. 

 Ins. Heft 187, Tab. 2. 



Evadne LOVEN. 



Compare S. L. LOVEN Evadne Nordmanni, ein bisher unbekanntes Ento- 

 mostracon, in WIEGMANN'S Archiv f. Naturgesch. 1838, pp. 143 166. 



Daphnia MUELL. (and Lynceus ejusd.). Feet ten, included in 

 shell, the eight anterior foliaceous, ciliated. Larger antennas bifid, 

 with branches having from two to four joints. 



Sp. Daphnia pulex LATR., Monoculus pulex L., SWAMMERDAM Bill. nat. 

 Tab. 31, figs. I in, MUELL. Entomostr, Tab. xn. figs. 4 7, DESMAREST 

 Crust. PI. 54, figs. 3 5 (borrowed from the figures of STRAUS) ; the 

 branched water -flea. This species is reddish, especially in spring, and from 

 its abundance may give a red colour to the water, or cause an apparent 

 change of it into blood, of which SWAMMERDAM adduces a remarkable 

 example, bl. 89, 90. 



In the genus Lynceus MUELL. there is a black spot in front of the eye ; 

 the antennae are usually very short. To these belongs Lynceus sphcericus, 

 &c. EDWARDS counts some of the species of Lynceus MUELL. in the 

 genus Daphnia. BAIRD adopts here different sub-genera, as Macrothrix, 

 Eurycerus, Chydorus LEACH, Camptocercus, Acroperus, Alona, Pleuroxus, 

 Peracantha (Ann. and Magaz. of Nat. Hist. Vol. xi. pp. 81 95, 1843), 

 Bosmina (ibid. Vol. xvn. 1846, pp. 410 413). 



Compare on this genus H. E. STRAUS Memoires sur les Daphnia, M6m. 

 du Museum, v. 1818, pp. 380 425, PI. 29; vi. 1820, pp. 149 162; 

 also W. BAIRD, Annals and Magaz. of Nat. Hist. I. 1838, pp. 245 256. 

 PL ix. 



Acanthocercus SCHOEDL. 



Compare J. ED. SCHOEDLER, Ueber Acanthocercus rigidus, ein bisher unbe- 

 kanntes Entomostr aeon. ERICHSON'S Arch. f. Naturgesch. 1846, s. 301 

 374, Taf. xi. xn. 



Genus Latona STRAUS, with bifid antennae, differs from Daphnia. 

 Sp. Daphnia setifera MUELL. 



OEDER VI. Phyllopoda. 



Feet lamellose, branchial, in eight pairs or more : in some, other 

 aatatory feet besides inserted behind the former. Two compound 



yes. 



Family XII. Branchiopoda. Body naked, without shell. Eleven 

 pairs of branchial feet. Two eyes petiolated and a frontal ocellus 

 essile. 



VOL. I. 41 



