6 A .REVISION OF THE BRITISH SPECIES OE 



to the antennas. The measurement given by continental authors 

 is about twice that of British specimens. 



C. elongatus was found plentifully in a gathering sent to me 

 by the Rev. Dr. Norman, F.R.S., from "pools near Broomley 

 Lough, Northumberland." This is the only British habitat 

 known to me. 



b. Anterior 



a. Reaching, when reflexed, beyond the posterior margin of the 

 first somite. 



2. Cyclops signatus, Koch (PL II., rig. 5). 



Antenna with serrated ridge. 



1820. Monoculus quadricornis albidus, Jurine (3), p. 44, pi. II., 



figs. 10, 11. 

 1841. Cyclops signatus, Koch (4), H. 21, tab. YIIL 

 1850. ,, quadricornis var. c, Baird (7), p. 203, 



pi. XXI V., fig. 5. 

 coronatus, Claus (13), p. 29, pi. II., figs. 1—11. 

 Claus (18), p. 97, pi. II., fig. 16; 

 pi. X., fig. 1. 

 signatus, G. 0. Sars (20), p. 33. 

 coronatus, Lubbock (19), p. 199. 



Fric(24), p. 218, fig. 11. 

 Clausii, Poggenpol (26), p. 70, pi. XV., 



figs. 4-14. 

 signatus, Uljanin (28), p. 29, pi. IX., figs. 6-11, 



pi. XL, fig. 8. 

 coronatus, Hoek (29), p. 12, pi. III., figs. 1-11. 

 signatus, Brady (32), p. 100, pi. XVII., 



figs. 4-12. 

 ,, var. fasciacornis, Cragin (40), p. 3, 

 pi. II., figs. 1-14. 

 Daday. (44), p. 208. 

 Vosseler (46a), p. 189, pi. IV., 



figs. 1-5. 

 Antenna with simple ridge. 



1820. Monoculus quadricornis fuscus, Jurine (3), p. 47, pi. III., 



figs. 2-4. 

 1850. Cyclops quadricornis, var. b. Baird (7) , p. 202, pi. XXIV., 



fiff. 4. 



1857. 

 1863. 



1863. 

 1863. 

 1872. 

 1874. 



1875. 



1876. 



1878. 



1883. 



1885. 

 1886. 



1857. 

 1863. 



1863. 

 1863. 

 71 



tenuicornis, Claus (13), p. 31, pi. III., figs.1-11. 

 „ Claus(18),p.99,pl.I.,fig.3; pl.IL, 



fig. 17; pi. IV., fig. 5. 

 annulicornis, G. O. Sars (20), p. 34. 

 tenuicornis, G. 0. Sars (20). p. 33. 



