308 7 he Irish Naturalist. . October, 



Cyclops albldus, Jurine (ahrntluarnis, Koch).— Clifden ; The Rosses, 



Co. Sligo ; Rossmore, Monaghan. 

 C. serrulatus, Fisch.— Clifden and Kylemore ; Rossmore, Cornacassa, 



Bragan. Co. Monaghan ; ly. Erne, L. Mask. ?J 



Van varius— The Rosses, Sligo. 

 C. praslnus, Fisch. — Rossmore, Monaghan. 

 C. flmbriatus, Fisch. — Rossmore, Cornacassa, Bragan, in Co. 



Monaghan. 



HARPACTID^E. 



.. 



Canthocamptus staphylinus, Jurine. — Drumreaske. 

 C. sp. (?) — Ballinahinch, Conuemara ; Rossmore and Cornacassa, 

 Monaghan. 



CALANIDvE. 



Dlaptomus Iaticeps, G. O. Sars. — This handsome species was 

 described and figured by Sars 1 as inhabiting several mountain lakes 

 in Norway. Lilljeborg gives Jemtland as a Swedish habitat. 

 Schnieil refers to it as related to the D. salinus, Daday, group of 

 Diaptomus, but does not include it in the German list of Copepoda. 2 

 Mr. T. Scott mentions D. Wierzejskii. a nearly allied species, as in- 

 habiting several lakes in Scotland. But apparently until I discovered 

 it in L. Mask, D. Iaticeps, Sars {iion de Guerne and Richard), was not 

 known as indigenous to the British Isles. The Rev. Canon Norman 

 kindly identified my first capture, and I have since carefully com- 

 pared several specimens with the descriptions and figures given by 

 vSars and Schmeil, and find the characters unmistakeable. It is 

 very abundant in the plankton both of L. Mask andL. Corrib, and its 

 Prussian blue colour makes it very conspicuous in the plankton, and 

 a beautiful object under the microscope. I also have met with a 

 single specimen in shallow lakelets at The Rosses, in the west of 

 Co. Sligo. We have here an additional link to the Scandinavian 

 fresh-water fauna. 



Dlaptomus gracilis, Sars. — Common in the lakes of Connemara ; 

 Irisdoonvarna lake, Co. Clare ; Glencar, Sligo : Rossmore and 

 Drumreaske, Monaghan; and very abundant in L Neagh, L. Erne, 

 L. Mask. L. Corrib, L,. Ree, &c. 



BRANCHIURA. 



Argulus foliaceus, L,. — L. Arrow, abundant; L. Neagh. not rare; 

 Drumreaske, Monaghan ; L. Oughter. 



Drumreaske, Monaghan. 



1 "Account of the Crustacea of Norway," p. 90, PI. lxi. 



2 " Deutschlands freilebende Susswasser Copepoden." Dr. Otto 

 Schmeil. iii. Teil, p. T74, taf. xiv., figs. 1-2. 



