ORTHOPTI'^RA— LOCUST ARI^F.. 231 



cells and even of the veins, is heavily blotched with irregular spots of paler 

 or deeper brown. The largest and deepest of the spots is central, following 

 the here approximated radial and ulnar veins. 



Length of tlie fragment, 8.5""; breadth of the s?me (probably nearly 

 the breadth of the base of the wing), 12.5"". 



Florissant. Two specimens, Nos. 1724, 2844. 



Subfamily CONOCEPHAI.ID.E StM. 



Although unknown in the European Tertiaries, this subfamily of locus- 

 tarians, pretty well developed in the southern half of the United States, and 

 far more so than in Europe, is represented by two forms from the Tertiaries 

 of Florissant, not distantly allied to forms still existing in our country. 

 (July, 1884.) 



ORCHELIMUM Ser^^lle. 



This genus, not before found fossil, and represented in North America 

 by a considerable number of species, especiall}- in the warmer portions of 

 the United States, is found in the shales of Florissant, a large species hav- 

 ing been disinterred. In its broad sense the genus is widely distributed 

 over the globe, but in a narrower one, in which our fossil will fall, it is, I 

 believe, peculiar to America. (July, 1884.) 



Orchelimum placidum. 



PI. 17, Figs. 10 ( 9 ), 18, 10 ( 5 ). 



Though obscurely defined, especially in the very parts which are 

 necessary to examine for close determination, the specimens at hand have 

 so clearly the aspect of an Orchelimum that we may safely consider them 

 as belonging to that modern genus, which Stal unites with Xiphidium. 

 The species is a ver}^ large one, larger even than O. concinnum Scudd., 

 which is the largest known to me, and has the angulated fastigium (seen 

 on a side view) and retreating face characteristic of the genus. The folded 

 tegmina and Avings extend some distance beyond the abdomen, and the ovi- 

 positor, which is well preserved and permits one to see that the upper and 

 lower blades are of equal length, is peculiar for its length and bluntness of 

 tip. It is also much slenderer than in 0. concinnum and less curved, in 

 which respects it approaches Xiphidium. 



