102 ANNUAL REPORT. 



Daphnia pennata, Muller, Entomost., t. 12, f. 4-7. 



Bosc, Man. d'Hist. Nat. des Crust., ii., 280. 



Schrank, Faun. Boic, iii., 264. 



Monoculus pulex arborescens, Linn. Syst. Nat.. 4th Edit., 96. 

 Pulex ■axborescens, Swammerdam, Hist. Nat. Ins. Gen., 76, 1. 1, 



f. o. b. c. Biblia Natures, 86, t. 31, f. 1-3. 



Goeze Naturfoscher, pt. 7. 



• Monoculus pulex ramosus, De Geer, M^m. pour servir a FHist. 



Ins., vii., 442. 

 Daphnia ramosa, Koch, Deutsch, Crust., h. XXXV., t. 18. 

 Daphnia media, Koch, Deutsch. Crust., h, XXXVII . t. 1. 

 Daphnia ephippiata, Koch, Deutsch. Crust., h. XXXV t. 16. 

 Puckron branchu, Trembley. 



Water-flea with branching' horns, Baker, Empl. for Micros. 

 Pou aquatique, JobJot, Observ. d'Hist. Nat. 

 Le Perroquet d'can, Geoffroy, Hist, abr^g. Ins. 

 Vermes minimi rubri, Merrett, Pmax Res. Nat. Brit. 

 Ammaletti aquatici, Redi, Asservaz'oni. Opere. 

 Monoculus, Bradley, Phil. Occ. of Works of Nature. 

 Le Puceron verdatre, Ledermuller. 

 Var. 1. Daphnia longispina, Muller. 



Latreille. 



Bosc. 



Ramdohr. 



Lamarck. 



Straus. 



Demarest. 



M. Edwards. 



Koch. 



Monoculus longispinus, Fahricius. 



Manuel. 



De Geer. 



Schoeffer. 



Var. 2. Daphnia magna, Straus. 



Demarest. 



M. Edwards. 



Description. — Carapax oval or sub- quadrangular, transparent, more or less 

 reticulated on all or part of the surface. Head large, more or less beaked. Su- 

 perior antennae very small. Inferior antennae strong and long. The superior 

 antennae have five small setae at the apex, while the inferior pair are armed with 

 the usual complement of setae, which in this species are finely plumose. 



The'color of this animal, which is our commonest and one of the largest spe- 

 cies, is dependent upon the food taken into the stomach, which extends through 

 nearly the whole length of the body in all the species. When feeding upon 

 clean vegetation the intestinal canal is of a brilliant green hue, while at othe^ 

 times it is dark or brownish. In England they are often of a bright red color 

 throughout, |but I have never met with such here. 



The carapax is terminated posteriorly by a serrated spine, which is variously 

 situated, and varies also with the age of the animal. In one variety the spine is 

 situated at the upper posterior angle while in others it sprinss from the centre of 

 the^posterior aspect. In the young the spine is long, almost equaling sometimes 



