ENTOMOSTRACA OF MINNESOTA. 195 



Daphuia veiitricosa Hellich. 



Hellich '77; Elymanu '87. 



A large pelagic species without the toothed comb of the claw. The 

 head is depressed, small, with rather protuberant front and long beak 

 inclined caudo-ventrad. The short oval shell is deeper than the head, 

 well rounded above and below. Spine long and straight, springing 

 from the middle of the caudal margin. The antennal sette are short 

 and thick and have the first segment longer than the second. The 

 first abdominal process is twice as long as the second, with which it is 

 united. The post-abdomen narrows toward the end and is hairy lat- 

 erally. Anal spines 14. Claws with setai. Length 2.28 mm. 



Dapliiiia cavidata Sars. 

 Fischer '54 (longispina). 



A large species without basal spines upon the claws. Head some- 

 what depressed, about one-third as long as the body, ventral margin 

 slightly concave; beak long, inclined caudo-ventrad. Shell oval, 

 with no depression between body and head. Spine long, springing 

 from the middle of the caudal margin. Eye near margin of head, 

 with few crystallines. Anteunte with short thick setae whose basal 

 segment is longer than the second. Post- abdomen narrowed toward 

 the end. Anal spines 9 to 12. Claw with a row of setae on the con- 

 cave, and two spines on the convex aspect. The two cephalic 

 abdominal processes united. Length 2.3 to 2.67 mm. 



This species is said to resemble T). longispina. Ifc would appear to 

 be closely related to B. veiitricosa. 



* Daphiua hyalina Leydig. 



Plates XXII, Figs. 7, 8; XXVII, Fig. 6; XXXV, Fig. 16; XLIX, Figs. 3-5; 



LIII, Figs. 1-4. 



Leydig '60; Sars '64 (galeata); Hellich '74 (gracilis); P. E. Mueller '68 (pellucida); 

 Birge '78 (kevisj; Ilerrick '83 



The general form and appearance down to the minute details in 

 this species are similar to I), l-ahlhergensis, with which it is almost 

 always associated, except the head which is subject to an astonishing 

 range of variation. A comparison of Figs 1 and 5 of Plate LIII^ 

 which were drawn by camera upon the same slide, illustrates the simi- 

 larity. The body is pellucid. Shell, sub oval, with long, straight, 

 toothed spine as long as the body without the head, and inserted high 

 up. Post-abdomen narrow with discrete processes, anal teeth about 



ten, terminal claw finely fringed or smooth. Eye small, either near 

 13 



