524 History of British Entomostraca. 
ment, beirtg 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. l.-~Cypris pubera Plate XVI. Fig. 1-13. Testa ovata 
reniformis, strigis viridibus obliquis ; tomentosa* 
Habitat. Fotffid In Berwickshire : neighbourhood of London, &c. ; common. 
Synonimes, Sfc Baker, Employment for Microscope, p. 387, plate 15, fig. 8 ? 
1753. 
Sordid insect. Midler, Philosoph. Transact. Vol. Ixi. p. 230, tab. 7, fig. 4-7. 
1771. 
Cypris pubera, Do. Zoolog. Danic. prodromus, p. 196, No. 2382, 1776. 
Monoculus ovato-conchaceus, De Geer, Memoires pour servir, &c. V. vii. p. 
476, pi. 29, fig. 6-7, 1778. 
Cypris pubera, Mutter, Entomostraca, p. 56, tab* v. fig. 1 5, 1785. 
Monoc. Conchaceus, Linn. Syst. Natur. cura Gmelin, 3003, No. 7, 1788. 
Mon. Conchaceus, Manuel, Encyclopedic 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. 12, 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. 
