126 BRITISH ENTOMOSTRACA. 
1. Chydorus sph^ericus. Tab. XVI, fig. 8. 
Lynceus sphjsricus, Muller , Zool. Dan. Prod., No. 2932, 1776; 
Entomost., 71, t. 9, f. 7-9. 
— Latreille , Hist. gen. Crust., 207. 
— Lamarck , An. s. Yert., v, 128, No. 3. 
— Desmarest , Cons. gen. Crust., 377. 
— Baird , Trans. Berw. Club, i, 100. 
— M. Edwards, Hist. Crust., iii, 386. 
— Pritchard, Micros. Cab., t. 8, f. 3. 
— Koch, Deutsch. Crust., h. xxxvi, t, 13 {not 
h. viii, t. 2.) 
Monoculus sph.®ricus, Gmelin, Linn. Syst. Nat. 3008, No. 60. 
— Jf^^,Encyc.meth.,vii, 732, t. 268, f. 15-17. 
— Fabricius, Ent. Syst., ii, 497. 
— Jurine, Hist. Monoc., t. 16, f. 3. 
Monoculus inpusorius (Kleinster Schildfloh), Enum. Insect. 
Aust., 536. 
— Fichhorn , Beyt. Naturg., t. 3, f. d* 
Chydorus Mulleri, Leach, Enc. Brit. Supp., art. Annulosa, 1816 ; 
Diet. Sc. Nat., xiv., 541. 
Chydorus sph^ricus, Baird, Ann. and Mag. Nat. Hist., ii, 89, t. 2, 
f. 11-13,1843; Trans. Berw. Nat. Club, ii, 150. 
Shell round, smooth, slightly ciliated on anterior 
margin, of an olive green colour. Inferior antennae or 
rami very short ; anterior branch has four setae, three 
springing from the extremity of the last articulation, 
and one from the extremity of the second ; poste- 
rior branch has only three from the last joint. Intestine 
convoluted, having one complete convolution and half 
another. 
Abdomen jointed, and having two stout claws at its 
end ; the intestine passing through the joint, and termi- 
nating in the anus near the claws. 
Eye areolar ; its accompanying black spot pretty large, 
and situated just above the root of the superior antennae. 
* Perhaps this may be a new species. Muller quotes this figure of 
Eichliorn for his L. trigonellus, but it appears to me to be quite distinct. It 
resembles the sphnericus in shape, except that the inferior extremity of the 
shell is pointed. Should it prove a new species, we would propose to name it 
Chydorus Fichhorni. 
