ENTOMOSTKACA OF MINNESOTA. 



97 



Outer ramus 



Outer ramus 



Outer ramus 



FiEST Foot. 

 ex. 2 spines. 



ap. 2 sette. Inner ramus 



in. 2 setae. 



Second and Third Feet. 

 ex. 2 spines. 



ap. 1 spine, 1 seta. Inner ramus 



in. 3 setse. 



Fourth Foot. 

 ex. 2 spines. 



ap. 1 spine, 1 seta. Inner ramus 



in. 3 seise. 



ex. 

 ap. 

 in. 



ex. 

 ap. 

 in. 



1 seta. 

 1 spine, 

 3 seise. 



1 seta. 



1 seta. 



1 spine, 1 seta. 



3 setfe. 



1 seta. 



2 spines. 

 2 setae. 



''The fifth foot is two jointed, the basal joint is short and bears a 

 tubercle carrying a seta 0.06 mm. long, the terminal segment is terete 

 and bears a spine 0.10 mm. long apically and another as long upon the 

 middle of its inner side. The cement gland is of peculiar shape, 

 resembling that of G. j)areus exactly. The last segment of the abdomen 

 is spiny upon the posterior margin above. The color is usually pale, 

 but may be ornamented with bluish suffusions. 



"Though closely allied with the species in America identified with 

 Sars' C. oithonoides there can be no doubt that two forms occur, this 

 one being nearly exactly like the species described by Hoeck as G. 

 leeuwenhoeJdi. The description and drawings are given as a basis upon 

 which to distinguish other allied species. The form from the Southern 

 States originally called G. tenaissimus is probably this species, though 

 possibly distinct." 



I have quoted our own original descriptions, correcting misprints 

 in the armature of the feet, which was, however, correctly given in 

 the figures. Schmeil's figure of the armature of the antennae is faulty 

 in not representing the teeth upon the lamina although the excision 

 is clearly shown. 



The form described in the previous edition as G. oithonoides Sars, 

 has not been reexamined and I am inclined to believe that it is but a 

 small pelagic form or variety of the typical G. leuekarti. Gyclops oitho- 

 noides is essentially a brackish water form and with its variety hyalina 

 Eehberg, and (7. dyhoivskii Schmeil, constitutes a very close group 

 whose members are quite variable and occur under such conditions as 

 to lead one to suppose that they constitute a compound specific group 

 whose members have not yet attained their autonomy. 



The original description of the American form is appended: 



"This most interesting species occurs under peculiar circumstances. 

 It is perhaps the rarest member of the genus, and seems, beyond a 

 doubt, nocturnal in its habits. It was first found by Sars in saline 

 water, and named, on account of its slender form, from the marine 

 Oithona. A similar species which, though about half as large, is 

 hardly distinct, was found by Eehberg near Bremen. Eehberg men- 



