83 



for their swollen liind thighs, enabliug them to spring to great distances 

 It appears to belong to the group of Oedionychifes Chap., in which the 

 last tarsal joint has a more or less prominent bulbous expansion on the 

 hind legs; but it differs from any of the genera described by Chai)uis 

 in the nature of this expansion, as well as in other tarsal peculiarities. 

 The basal joint of these hind tarsi is moderately long and cylindrical, 

 scarcely larger at the apical than at the distal extremity ; the second 

 and third joints are snbequal, the latter slightly the larger, together as 

 long as the basal joint, moderately lobate, the lobes pointed ; while the 

 apical joint is nearly as long as all the other joints combined, enlarges 

 gradually from base to apes, so as to be fully two or three times as large 

 at the apical as at the distal extremity, and bears a pair of exceed- 

 ingly long and slender, apparently simple, very slightly curved claws, 

 nearly half as long as the apical joint itself. In other respects it closely 

 resembles the genus Oedionychis Latr. 



19. Oryctoscirtetes protogwum. — A single specimen, pretty well pre- 

 served, and exhibiting the dorsal surface, was obtained by the United 

 States Geological Survey of the Territories near Castello's ranch, South 

 Park, Colorado. The head is pretty large, nearly as broad as the 

 prothorax, the eyes moderately large, apparently circular, with large 

 facets, their average diameter being nearly .02'"™. The prothorax is broad, 

 with well rounded, somewhat convex sides and front lateral angles, the 

 anterior margin considerably concave ; the posterior lateral angles are 

 rectangular, and there is apparently a median furrow on the posterior 

 half, although the appearance may be due to the crushing of the fossil. 

 The surface of the prothorax, and also of the elytra, is very delicately 

 granulate ; the elytra are also furnished very indistinctly with several 

 (five or six?) longitudinal ridges, straight and equidistant. The fore 

 femora are swollen as well as the hind pair, but the middle femora can- 

 not be seen. Both middle and hind tarsi are fully four-fifths as long as 

 their tibise. 



Length, 5"""; breadth, 2.25"""; width of head, 1.25""'; of prothorax, 

 1.8"""; length of same, .92'""'; of elytra, 3"'"'; of middle tibite, 1.34"""^; 

 of middle tarsi, 1.12"^™ ; of middle claws, .18"™ ; of hind femora, 1.32™"' ; 

 breadth of same, .48™™ ; length of hind tibite, 1.4™™ ; width of same, 

 .18™™; length of hind tarsi, 1.14"'™ ; of first joint, .32™™; of fourth joint 

 (excl. claws), .48™™ ; of claws, .22™'" ; breadth of fourth joint at tip, .1™™. 



20. Trypodendron impressus. — This species is represented by a single 

 specimen, showing the prothorax and elytra, and was obtained from the 

 Green Eiver Beds in Western Wyoming by Mr. Eichardson. It is 

 slightly larger than T. retusus (Le C), but has the prothorax punctured 

 as distinctly as the elytra, and the punctures on the elytra show but 

 a slight tendency to a longitudinal arrangement. The punctures of the 

 prothorax are longitudinally obovate, a very little more frequent than 

 on the elytra, equally distributed throughout; on the elytra they are 

 also equally distributed, but circular, about 0.04""" iu diameter, and aver- 

 age .1'"™ in distance apart: they have but an obscure longitudinal 

 arrangement into nineteen or twenty rows ; and the successive punc- 

 tures of each row are at about the same average distance apart as those 

 of two coutiguous rows. 



Length of prothorax, 1.28'""; height of same, 1.44™'; length of elytra, 

 2.8"'™; breadth of same, 1.24™™. 



21. Sitones grandccvns. — A single specimen, very poorly preserved, was 

 found by Mr. Eichardson on Green Eiver, at the crossing of the Union 

 Pacific Eailroad. Little can be seen beside a vague outline of the form 

 of the body, with a broken rostrum; the eye is large, obovate, longi- 

 tudinally disposed, 0.42""* long, and 0.25™"' broad ; the elytra are fur- 



