176 D. J. SCOURFIELK ON ENTOMOS'IM.'ACA. 



during the colder parts of the year. I have no record of it 

 from the " Perch Pond." 



Cyclops viridis, Jiirine. Both the " gigas " and " hrevicornis " 

 varieties of this species are common at Wanstead Park. 



Cyclops serrulatus, Fischer. Could any British local list be 

 complete without this ubiquitous and well-marked species ? 



f Cyclops macrurusy G. 0. Sars. — The specimens here referred 

 doubtfully to C. Tnacriirus were all males, and although possess- 

 ing very long caudal rami, without serrulated outer margins, 

 may really have belonged to C. serrulaUis. The typical males 

 of the latter species, by the way, are, so far as I have observed, 

 always destitute of serrulations on the caudal rami. 



Cyclops afinis, G. 0. Sars. 



Cyclops phaleratus, Koch. 



Cyclops fimhriatus, Fischer. The three foregoing species are 

 the least common of the genus at Wanstead Park. It is worth 

 notice that neither of them has ever been taken from May to 

 August inclusive. 



Canthocamptus mmiitus, 0. F. Miiller (Brady, Monograph of 

 British Copepoda, Vol. ii., Ray Society, 1880, p. 48, PI. XLIV). 

 All the Wanstead Park forms seem to belong to this common 

 and widely distributed species. 



