620 GEOLOGICAL SUEVEY OF THE TERRITOEIES. 



in productus. Supraanal plate with fewer larger teeth. Carapace shorter. 

 Length, exclusive of caudal filaments, 1 inch. Greenland and Cape 

 Krusenstern (Eichardsou). 



Apiis. — Antenniform maxillipeds long; telson squarish. 



A. ieqnalis, Pack. (Amer. Jour. Sc, 1871), (Fig. 10). — $ . Carapace 

 longer than in any of the other species; eyes larger.- Number of seg- 

 ments behind the posterior edge of the shield, 23. Length of body (ex- 

 cluding caudal filaments), 1.15 inches. 



2 . The telsou has 5 median spines, and is shorter, while the caudal 

 filaments have more numerous and shorter spines than in A. Newberryi. 

 The under side of the telson is much smoother than in A. longlccmdatus, 

 and the outer gill of the first maxilliped is a little longer and more 

 acute. Number of segments beyond the hind edge of carapace, 25. 

 Length of body alone, 1.07 inches. Plains of Eocky Mountains, Kan- 

 sas ('?), and Matamoras. 



Apus Newberryi, Pack (Amer. Journ. Sc, 1871). — 9 . Differs chiefly 

 fi'om A. longicaudatus in the shorter maxiilipeds, and much longer, 

 smooth telson, with 3 instead of 4 median spines, and in the smooth, 

 finely-spiuulated caudal stylets, while the carapace is longer. Number 

 of segments behind the posterior edge of carapace, 29. Length of body 

 (excluding caudal filaments), 1.78 inches. Utah. 



Apus Lucasamis, Vack. (Amer. J ouvn. Sc, 1871). — ^. Closely allied 

 to A. longicaudatus. Maxiilipeds shorter and smaller ; telson longer, 

 with 3 median spines. Anal stylets less spiny than in A. longicau- 

 datus. Number of segments behind the posterior edge of the carapace, 

 33. Length, of body alone, 0.94 inch. 



$. Carapace longer than iu S , and caudal filaments not so heavily 

 spined. Number of segments behind posterior edge of shield, 29. Length 

 of body alone, 0.80 inch. Cape Saint Lucas. Males from Kansas. 



Apus longicaudatus, Leconte, $ and 9 (Annals N. Y. Lyceum, IV 

 155, 1846), — In this species, the body is larger and carapace is shorter 

 than in any of the others. James's A. obtusatus (Long's expedition) is 

 probably this species. The 9 differs from males in the shield being 

 longer, with 28 segments beyond the end of the shield, and the under 

 side of the telson is smoother, but above, as m $ ; ovisac, 0.10 inch in 

 diameter. Length of bodj^, 1.50 inches; of carapace, 0.60 inch. The caudal 

 filaments are smaller and more coarsely spined than usual. Eocky Mount- 

 ains, near Long's Peak (Mus. Yale Coll.) ; Texas. Pools near Yellow- 

 stone Eiver, Dr. Ilayden. "Found in immense numbers iu a small 

 shallow lake on the high plateau between Lodgepole Creek and Crow 

 Creek, northeast of Long's Peak." — (Leconte.) 



Family Branohipodid^. — Body long and slender, with no carapace; 

 eyes stalked ; second pair of antennae adapted for clasping ; 11 pairs 

 of branchial (respiratory) feet. Female with a large eggpouch attached 

 at the base of the abdomen. Prof. A. E. Verrill, in his valuable 

 "Observations on the Phyllopod Crustacea of the Family Branchi- 

 pidse " (Proc. Amer. Assoc. Adv. Sc, July, 1870), has given the characters 

 of the genera and species, and I give abstracts of his diagnoses of the 

 generic and specific characters, with the addition, however, of descriptions 

 of Streptocephalus Texensis and Branchinectes Coloradensis, which have been 

 described since the publication of his paper. 



Artemia. Clasping organs (second antennae) three-jointed ; egg-sac 

 short, broad ; living in saline or alkaline waters. 



Artemia gracilis, Verrill (Fig. 11, enlarged). — Body slender; in the 

 male about 0.3 inch long ; in the female, 0.4 inch. Claspers of the male 

 relatively long and powerful ; first joint thickened, with a distinct angle 



