ENTOMOSTRACA OF MINNESOTA. 63 



*Diaptoimis signicaiidatus Lilljeborg. 

 Plates VIII, Fig. 13; IX, Fig. 10. 

 De Guerne and Richard '89. 

 A small species found at great altitudes ia the Sierra J^evada 

 Mountains of California and forming an obvious transition toward 

 JSjylschura. Form rather robust, greatest width at the second segment. 

 Last two segments of the thorax confluent, projecting into lateral lobes 

 bearing small teeth. The fourth thoracic segment with a slight dorsal 

 gibbosity. First abdominal segment expanded and spined anteriorly, 

 and bearing a large retrorse process on the right side posteriorly. 

 Second segment short. Caudal stylets about half again as long as 

 wide. Antennse 25-jointed, extending little beyond the stylets. An- 

 tepenult segment of the right male antenna with a small hook. Fifth 

 foot in the female with one-jointed inner ramus as long as the basal 

 joint of the outer ramus. The terminal segment of the outer ramus is 

 obsolescent. The external ramus of the right foot of the male bears a 

 hyaline lamina on the inner aspect of the basal segment. Second 

 segment more than twice as long as the preceding. Claws simply 

 arcuate. Accessory spine nearer the end than the base of the second 

 segment. Inner ramus wide and acute, shorter than the basal segment 

 of the outer ramus. The left foot has a slender inner ramus, longer 

 than the basal segment of the outer, whose apical joint is pilose and 

 armed with two spines. Length of female 1.5 mm. ; of male 1.3 mm. 



Diaptomus incong^ruens Poppe. 



Plate VIII, Fig. 6. 

 Poppe '88; De Guerne and Richard '89. 



A Chinese species of moderate size, characterized by the fact that 

 the projecting angles of the last thoracic segment are dissimilar on the 

 two sides and the possession of a broad mucronate process on the right 

 side of the first abdominal segment. The antennte extend far beyond 

 the stylets. The antepenult joint of the right male antenna bears a 

 hyaline lamella ending distally in a small hook. The fifth foot of the 

 female has a one jointed inner ramus as long as the basal joint of the 

 outer ramus. The apical joint is distinct and the claw serrate. The 

 inner ramus of the right foot of the male is one jointed and that of the 

 left foot two jointed. The terminal segment of the outer ramus of the 

 left foot has two spines apically and a ciliated plate within. Length 

 of female 1.4 mm. 



Diaptoiuiis gibber Poppe. 



Plate VIII, Fig. 1. 



De Guerne and Richard '89. 



A decidedly unique form from Brazil. The last thoracic segment 

 forms on either side a bi spinose process, the two being dissimilar. 

 The first segment of the abdomen is expanded proximad and bears on 



