ENTOMOSTKACA OF MINNESOTA. 59 



Diaptomus saliuus Daday. 



Plate VIII, Fig. 3. 



Daday '85^; De Guerne and Richard '88^ (D. blanchardi), and '89. 



This species was found by Daday in Forda, Hungary, and is identi- 

 fied with the form subsequently described by De Guerne and Richard 

 as I), hlanchardi. It may be recognized by the sharp spines on the 

 right side of the first and second segments of the abdomen (affording 

 a transition toward Heterocope and Upischura), and also by the pecu- 

 liar armature of the male fifth feet, which have accessory processes 

 upon the basal joint of the right limb and the second segment of its 

 outer ramus. The apical segment of the outer ramus of the fifth feet 

 of the female are unusually well developed. The antepenultimate 

 segment of the male geniculate antenna has a very long straight pro- 

 cess, longer thau the two following segments. Length of female 2.2 

 mm. The very short antennae and saline habitat further distinguish it. 



Diaptoiims laticeps G. O. Sars. 



Sars '63; De Guerne and Richard '89. 



This species, which is widely distributed in Europe, has the front 

 considerably dilated. The antennte are as long as the body. The 

 caudal stylets as long as the two preceding combined. The antepe- 

 nultimate of the geniculate antenna has a process shorter than the pe- 

 nultimate segment. The male fifth foot has armature similar to D. 

 salirms. Length 1.5 mm. 



* Diaptomus ininutiis Lilljeborg. 



Plate VIII, Fig. 9. 



De Guerne and Richard '89; Marsh '93 and '93. 



One of the smallest species of the genus, originally taken in Green- 

 land, but widely distributed in the northern regions. Slender, with 

 the greatest width behind the middle. The fourth and fifth thoracic 

 segments fused or more or less distinct in the old, with small mucron- 

 ate lateral lobes. First segment of the abdomen as long as the re- 

 mainder, expanded anteriorly and armed with small spines. Second 

 and third abdominal segments partly fused, the second very short. 

 Caudal stylets twice as long as broad. Antenmc 25 jointed, some- 

 what longer than the stylets. Antepenult segment of male antenna 

 with a long slender process, nearly as long as the two following seg- 

 ments and slightly hooked at the tip. The external ramus of the fifth 

 foot of the female is two-jointed, with a short claw, the inner ramus is 

 small and one jointed. The left fifth foot of the male is much shorter 

 than the right, and its apical segment is armed with a spiny pad and 



