ENTOMOSTRACA OF MINNESOTA. 321 



The feebly- curved post-'abdomen (Fig. 46) is stout and short. The 

 terminal claw is a little more than half as long as the abdominal 

 ramus. The adjacent claw is about three- fourths as long as the ter- 

 minal claw. 



Habitat: Cincinnati, Ohio (Turner, 213); Guanajuata, Mexico 

 (Herrick, 86); Albuquerque, New Mexico. 



Cypris virens Jurine. 



Plate LXXIV, Figs. 3-3e. 



1820.— 3Ionocuhis mens Jurine (98), p. 174; PI. XVIII, Figs. 15-16. 

 1838.— Cypris qibbenila Koch (102), H. XXI, 20. 

 1844.— " virens Zaddach (234), p. 35. 

 1844.— " pilosa Zaddach (234), p. 36. 



1850.— " irisiriain Baird (5), p. 152; Taf. XVIII, Figs. 1, la-li, 2-3. 

 1851.— " ornaia S. Fischer (63), p. 157; PI. IX, Figs. 7-10. 

 1853.— " v/rensLil)jeborg(118), p. 117; Taf. VIII, Fig. 16; Taf. IX, Figs. 4-5, 

 1868.— " virens Brady (18), p. 364; PI. XXIII, Figs. 23-32; PI. XXXVI, Fig. 1. 

 1868.— " 2^ubera Fric and Nekut (70), p. 46, Fig. 26. 

 1870.— " ventricosa Brady and Robertson (33), p. 12; PI. IV, Figs. 1-3. 

 1872.— " pubera Fric (69), p. 226. 



1874.— " virens Brady, Crosskey and Robertson (30), p. 124; PI. II, Figs. 27-28. 

 1887.— " RelenaMoQiez (135), p. 2. 



1887.— " virens C. L. Herrick (86), pp. 24-26; PI. VI, Fig. 3. 

 1889. — " virens Brady and Norraan (31), p. 77. 



1891.— " virens Wenzel Vavra (221), pp. 102-104, Fig. 3; Figs. 4, 4'^, 4^, 4^; 

 Figs. 5, 51-52; Figs. 36, 36i-36^ 



Only once have I encountered an American form which I supposed 

 was Cypris virens. Then the specimens were accidentally destroyed 

 before accurate drawings were made. Mr. Deming, however (Her- 

 rick, 86), claims to have found this species to be quite abundant at 

 Granville, Ohio. The following description is due to Mr. Deming. 

 I have taken the liberty to omit much that is merely generic and to 

 add, in brackets, some specific characters. 



"Valves sub-reniform, the two ends almost equal, the dorsal side 

 evenly curved, the ventral side sinuated, highest in the middle. The 

 valves are covered with minute hairs. The hinge-line is sinuated and 

 unbroken. The outer part of the shell is slightly lined. The shell as 

 seen on end is oval; seen from above, oblong-ovate. Lucid spots, 

 about seven in number, are found in about the centre of the valves; 

 these are oblong and irregular in shape, often pointing towards the 

 ventral margin. Isolated spots are found near the dorsal side. The 

 color is olive or yellowish green, with dark brown spots near the dorsal 

 margin and scattered throughout the shell. * ^< >i< * * ^i; * 



[The two biarticulate spines on the first mandibular process of the 

 first maxilla are smooth.] 



