103 



related, and in all probability stand in a close genealogical relation to each other; 

 but as long as no distinct transitions between them have been demonstrated to 

 exist, they must be kept apart. The true E. affims, Poppe, of which I have had 

 specimens for examination, is a much more robust form, and differs moreover, 

 at any rate in the female sex, in the larger size of the lateral expansions of the 

 last segment of the metasome, as also in the shape of the genital segment. The 

 specimen described by Prof. Lilljeborg as the male of his Temora velox, is 

 undoubtedly referable to the present species, and this is also the case with the 

 form recorded by Boeck as Temora velox, and that named T. inermis, the latter 

 supposed species being only founded on immature specimens, in which the lateral 

 expansions of the last segment of the metasome have not yet been formed. 



Occurrence. I have found this form both in the sea and in brackish 

 lakes and ditches round the greater part of the Norwegian coast. On the other 

 hand, I have never met with it in perfectly fresh water. At the Zoological Station 

 at Drobak, it is often taken close to the shore in comparatively salt water, and 

 I have also occasionally found it in plankton-samples taken in the Brevik Fjord. 

 I have come across it in quite extraordinary abundance in a brackish lake at 

 Kolvereid, Namdal, and this is the most northerly place where I have observed it. 



Distribution. Skane (Lilljeborg), Finnish coast (Nordqvist). 



44. Eurytemora lacustris, Poppe. 



(PI. LXX). 

 iH, Poppe, Zeitschr. f. wiss. Zool. Vol. 45. p. 278, PI. 15, figs. 10 13. 



SJTI : Temorella intermedia, Nordqvist. 



Specific Characters. Female. Body somewhat less slender than in E. 

 hirundoides, with the anterior division, seen dorsally, oblong oval in form, greatest 

 width exceeding y 3 of the length and occurring quite in front, across the middle 

 of the cephalosome, anterior extremity rounded, posterior somewhat contracted. 

 Cephalosome occupying about half the length of the anterior division, and exhi- 

 biting in the middle dorsally a slight cervical depression, and at the end a 

 well-marked knob-like prominence. Last segment of metasome scarcely at all 

 expanded laterally. Urosome rather slender, genital segment but slightly dilated 

 in the middle, anal segment fully as long, but much narrower, and perfectly 

 smooth above. Caudal rami not quite attaining the length of the 2 preceding 

 segments combined, but like them smooth above; seise of moderate length, that 

 of the outer edge scarcely shorter than the others, and situated at rather a long 



