Clare Island Survey — A carinida 39 21 



of swimming-hairs present on the legs, as compared with the lowland 

 Diplodontus dcspiciens ; the legs are also shorter, stouter, and are furnished 

 with more strongly developed claws (34). 



This variety is no doubt widely distributed. I have found it commonly 

 in the River Dodder and in various rivulets on the Dublin and Wicklow 

 mountains, as well as in other localities in Ireland. 



Megapus tener Sig. Thor. 



Carrownisky River near Louisburgh, Co. Mayo, July. 



A male of this little-known species occurred in the above locality, and I 

 have also taken both sexes in the Eiver Dodder near Dublin. 



Length of male about '66 mm. The epidermis is remarkably thick and 

 exceedingly finely lined ; front margin indented and furnished with very long 

 antenniform bristles. 



First pair of legs with the terminal segment short, stout, and less bent 

 than it is in M. spiiniptes. There are two swimming-hairs on the fifth segment 

 of the last pair of legs. In males from the River Dodder (Co. Dublin) the 

 last pair of legs are a little shorter and stouter, and swimming-hairs are 

 absent. The palps are more slender than the basal segments of the first pair 

 of legs ; the fourth segment, seen from above, is decidedly swollen, and its 

 dorsal surface is crowded with numerous short hairs ; sword-like bristle on the 

 inner side strongly developed. A figure of the male palp is given by 

 Maglio (16). 



The epimeral area is large ; between it and the hinder margin of the body 

 there are three pairs of large gland-openings with strongly chitinized 

 margins. 



The female may be easily recognized by the fact that the three genital 

 discs are arranged in a triangular form instead of in a linear row as they are 

 in M. spinipes. 



Distribution. — The ascertained range is Norway ; Germany ; Italy ; and 

 the British Isles. 



Megapus nodipalpis Sig. Thor. 



Clare Island, in a rivulet flowing from hills, June ; Bunowen River, 

 Louisburgh, July ; Croaghpatrick, June. 



This species occurs in rapid streams and is widely spread in Ireland. The 

 specimen found on Croaghpatrick is in the nymph stage. 



Distribution. — Norway; Switzerland; N. Italy; and Britain. 



