Diaptomus. 195 



Diaptomus sanguineus Forbes. 

 Plate I'll. Figs. 1-3. 



1876. D. sanguineus Forbes (17) pp. 15, 16 and 23, figs. 24, 



and 28-30. 

 1882. D. sanguineus Forbes (22) p. 647, pi. VIII, figs. 1-7, 



and 13. 

 1884. D. sanguineus Herrick (26) p. 138, pi. Q, fig. 12. 



" " minnetonka Herrick (26) p. 138, pi. Q, figs. 8-10. 



1889. " sanguineus DeGuerne and Kichard (32) p. 20, pi. 



IV, fig. 24. 



This species, which is found in pools in the spring months, 

 is readily recognized by the characters of the male antennae 

 and fifth feet. My specimens differ in minute particulars from 

 the figures given by Forbes ; the lateral spine on the terminal 

 joint of the outer ramus of the right fifth foot in the male is 

 nearer the distal end of the joint, while Forbes's figure makes 

 its position nearly median; the blunt spine on the inner angle 

 of the second joint of this foot is a little longer than the spine 

 at the outer angle, instead of shorter, as in his figure. 



D. minnetonka Herrick is probably a variety of B. san- 

 guineus. 



Diaptomus leptopus Forbes. 

 Plate III. Figs. 4 and 5. 



1882. D. leptopus Forbes (22) p. 646, pi. VIII, figs. 17-19. 

 1884. " longicornis var. leptopus Herrick (26) p. 140. 

 1889. " leptopus DeGuerne and Richard (32) pi. II, fig. 19, 

 pi. Ill, fig. 9. 



Forbes, in his description, states that the antepenultimate 

 segment of the right male antenna bears a small hook. I have 

 failed to find a hook in my specimens ; the segment is armed 

 only with a very inconspicuous hyaline lamella. DeGuerne and 

 Richard have also noted the absence of the hook. 



