524 History of British Entomostraca. 



ment, being almost constantly in motion, either swimming about 

 pretty rapidly by the united action of their antennae and anterior 

 feet, or walking upon the plants and other solid bodies floating in 

 the water. Instead of being, like the molluscous animals to which 

 they bear such a resemblance in external covering, fixed to one 

 place, and condemned to live amidst eternal darkness, they, says 

 Muller, " by opening their valves, enjoy light, and move at their 

 will — sometimes burying themselves in the mud, sometimes darting 

 through the water, the humid air of their sphere. If they meet any 

 unforseen object they conceal themselves all at once in their shells, 

 and shut the valves, so that force and address seek in vain to open 

 them."* 



Species. 



Sp. I. — Cypris pubera — Plate XVI. Fig. 1-13. Testa ovata 

 reniformis, strigis viridibus obliquis ; tomentosa. 



Habitat — Found in Berwickshire : neighbourhood of London, &c. ; common. 

 Synonimes, Sfc Baker, Employment for Microscope, p. 387, plate 15, fig. 8 ? 



1753. 

 Sordid insect. Muller, Philosoph. Transact. Vol. lxi. p. 230, tab. 7, fig. 4-7. 



1771. , 

 Cypris pubera, Do. Zoolog. Danic. prodromus, p. 198, No. 2382, 1776. 

 Monoculus ovato-conchaceus, De Geer, Memoires pour servir, &c. V. vii. p. 



476, pi. 29, fig. 6-7, 1778. 

 Cypris pubera, Muller, Entomostraca, p. 56, tab. v. fig. 1 — 5, 1785. 

 Monoc. Conchaceus, Linn. Syst. Natur. cura Gmelin, 3003, No. 7, 1788. 

 Mon. Conchaceus, Manuel, Encyclopedie Methodique, Hist. Nat. Tom. vii. p. 727, 



No. 39, pi. 266, fig. 27-30, 1792. 

 Mon. Conchaceus, Fabricius, Entomolog. Systemat. Tom. ii. p. 496, 1793. 

 Cypris Conchacea, Latreille, Hist. Nat. Gen. et Part, des Crust, et Ins. Tom. iv. 



p, 246, 1802. 

 Cypris Conchacea, Lamarck, Hist Nat. des Anim. sans Verteb. Vol. v. p. 124, 



No. 1, 1818. 

 Mon. Conchaceus, Rees* Cyclopedia, Art. Monoculus, 1819. 

 Cypris Conchacea, Leach, Edinburgh Encyclopedia, Art. Crustacea, Vol. vii. 



p. 388. 

 Monoc. puber, Jurine, Hist, des Monocles, &c. p. 171, pi. 18, fig. 1 — 2, 1820. 

 Cypris pubera, Desmarest, Consid. Gen. des Crust, p. 383, 1825. 

 Cypris tristriata, Baird, Transact. Berwickshire Nat. Club. p. 99, pi. iii. fig. 



13, 1835. 



There appears to me considerable obscurity amongst authors with 

 regard to this species. Muller's description agrees very well in most 

 respects, but his figure is decidedly bad. The figure given by Jurine 

 is so different from that given by Muller or his description of it, 



* Entomostraca. 



