86 A REVISION or THE BKITISH SPECIES OP 



only previous record of it is by Mr. Cragin, who found it at 

 Cambridge, U.S.A., very abundantly "in the dirty water of 

 the blind ditches connected with the artificial pond known as 

 " Grlacialis." It is curious that in both cases the animal was 

 found in ditches immediately connected with large sheets cf 

 water. 



I have had no opportunity of examining any but the spirit- 

 specimens of Dr. Norman's collection, but the following charac- 

 ters may be added as having been noticed by Mr. Cragin in living 

 specimens: "eye large, dark red; divided deeply by a median 

 constriction posteriorly. Ovisacs small, sub-oval, nearly or quite 

 meeting above the abdomen, and usually containing from five to 

 eight eggs. Animal dirty blue-green ; antennae lighter. Dark 

 green pigment masses are scattered beneath the integument in 

 various places, particularly along the anterior side of the first 

 antennae." 



Herrick, in his " Final Eeport on the Crustacea of Minnesota," 

 identifies this species with C. fluviatilis^ Herrick, but there are 

 several characters which prevent my accepting this view ; notably 

 that in C. fluviatilis, "the terminal segment of the antennae is 

 slightly but evidently hinged, and together with the pair preced- 

 ing, somewhat curved," and that the feet have the "terminal 

 spines strongly toothed." "The antennae," Herrick says, "are 

 long and much modified so as to resemble superficially the an- 

 tennae of Diaptomus." This can scarcely be said of the British 

 specimens which I ascribe to C. magnoctavus, and which agree 

 in every respect with the figures and description given by Cragin. 



E. Anterior antenna eleven-jointed. 



14. Cyclops affinis, G. 0. Sars (PL YIII., figs. 1-6). 



1863. Cyclops affinis, G. 0. Sars (20), p. 47. 

 1875. ,, ,, Uljanin (28), p. 36, pi. XL, figs. 3-7. 



1878. „ „ Brady(32),p.ll2,pl.XV.,figs.ll-14; 



pi. XXI Vb., figs. 10-15. 

 1880. ,, pygmceus, Eehberg (33), p. 546, pi. VI., 



figs. 3-6. 

 1886. ,, f#ms, Vosselcr(46A),p.l92, pl.VI., figs.1-3. 

 1891. ,, ,, Schmeil (66), p. 34. 



