EXTOMOSTRACA OF MENNESOTA. 315 



GENUS ERPETOCYPRIS Brady and Xorman. 1889. 



"General characters of the animal closely approaching those of 

 Oypris; but the setie of the third joint of the lower antennae are short, 

 not nearly reaching the apex of the terminal claws, and are not 

 plumose. The second pair of jaws have branchial plates as in Cypris. 

 The power of swimming is lost, and the habits of the animals, which 

 creep along the bottom, are thus very different from those of C^j^m." 

 (Brady and Norman). 



Erpetocypris minnesotensis (Herrick.) 

 Plate LXXII, Figs. 2-2h. 

 1887.— Ci/pr is minnesotensis C. L. Herrick (86), p. 28; PI. lY, Fig. 2. 



Length 1.60 mm. 



This species is closely related to Erpetocypris fasciata (O. F. Miiller). 

 In U. fasciata the caudal margin of the abdominal ramus is smooth) 

 but in U. minnesotensis it is pectinate. In U. fasciata the length is three 

 times the width, but in E. minnesotensis the length is two and one-half 

 times the width. 



The figures and the following description are from Professor Her- 

 rick (86). 



"From any of the American species it is at once known by the 

 great proportionate length of the valves, which are about two and 

 one-half times as long as broad. Lower margin nearly straight, gently 

 sinuous near the middle, dorsal margin gently curved, highest back 

 of the middle, then gently curved; color light, with two inconspicu- 

 ous dark transverse bands on either side at about the anterior and 

 posterior thirds; scattered hairs upon prominences are found near the 

 margins. Antennae (antennules) slender, seven-jointed, apex with 

 two very long and one short spine, penult segment with four long 

 setre, antepenult segment with two long plumose setiE above, preceding 

 segment with shorter sette; second antennse with the apical segment 

 very short and armed with one (!) serrate claw and a seta, the preced- 

 ing with two claws and a few short setse, antepenult segment with 

 three (four?) shortish setfe, not reaching end of claws; mandible with 

 strong lobed teeth and a large palp; first foot with a large claw; sec- 

 ond foot slender, ending in a small hook with a single weak seta; cau- 

 dal stylets rather short and wide, with two strongly serrated claws, 

 the other spines being obsolescent (!); posterior margin serrulated. 

 Lucid spots of the shell seven in number, two being minute. Length 

 of shell ].6 mm." 



Habitat: Minnesota (Herrick, 86). 



