284 



UNIVERSITY OF COLORADO STUDIES 



Fig. 46. — GraptoUberis 

 testudinaria. 



76 (73) Head not keeled. Beak long and slender. . . Genus Kurzia 

 One species in United States. Length, 0.6 mm. 



Kurzia latissima (Kurz) 



Sometimes listed as Alonopsis latissima Kurz. Greeley; 4,600 ft. [Widespread in United States 

 and Europe. 



Claw without spine in middle 78 



Beak directed forwards and somewhat turned up at the end, forming 

 a sort of snout. Head broader than body. 



Genus Graploleberis 



But one species in the genus. Length, 0.7 mm. 



Graptoleberis testudinaria. (Fischer) 



Boulder, Tolland, Twin Lakes; 5,250-10,800 ft. [Common all over 

 United States and Europe.) 



79 (78) Beak directed downward. Head not broader 

 than body 80 



80 (87) Free posterior margin of valves but little less 

 than greatest height of shell. 81 



81 (82) Post-abdomen broad and rounded and armed with many long and 



slender spines. Genus Leydigea 



One species in Colorado. Claw of 

 post-abdomen with a small basal spine. 

 Setae on keel of labrum small. Length, 

 0.9 mm. 



Leydigea quadrangularis (Leydig) 



Boulder; 5,200 ft. [All parts of United States and 

 Europe but not abundant.] 



82 (81) Post-abdomen not unusually broad 

 nor are the spines of great length. 



Genus Alona 83 



83 (86) Post-abdomen rounded at the end 

 and armed with a row of spines and a 



corresponding number of tufts of bristles 84 



(85) About 9 spines; the bristles long, some of them reaching well beyond 



the margin of the post- 

 abdomen. Length, 

 0.4 mm. 

 A lona rectangula Sars 



Boulder, Tolland; 5,400- 

 11,250 ft. [Widespread in 

 United States and Europe.] 



Fig. 47. — Leydigea quadi 

 (After LUljeborg.) 



ngularis. 



Fig. 48. — Alona rectangula. 



Fig. 49. — Alona a^nis. 



