340 STUDIES IN THE ISCHNOITERITES (ORTHOPTERA) 



proximal margin, with sides of emargination convex (Plate XVI, 

 fig. 3, A), bearing beneath on each side near the apex of the emar- 

 gination a minute chitinous projection armed dorso-distad with 

 close-set delicate microscopic teeth, which are directed cephalad 

 (Plate XVII, fig. 3); seventh dorsal abdominal segment in 

 greater part lying under sixth segment, but with a narrow, 

 medio-longitudinal, decidedly elevated ridge lying between the 

 armed projections of the sixth segment. Eighth dorsal abdom- 

 inal segment unspecialized. Cephalic femora with ventro- 

 cephalic margins armed with (usually about four) heavy, 

 elongate, well separated, proximal spines, succeeded distad by a 

 row of minute, closely set, piliform spines, which is terminated 

 distad by three heavy, elongate (in increasing ratio) spines. 

 Other ventral margins of femora supplied with widely spaced, 

 heavy, elongate spines. Median and caudal femora in addition 

 supplied with a single elongate genicular spine. Small arolia are 

 present. 



The Morio Group 



This group is very close to the Rufa Group. The two species 

 known to us differ from those of that group in their larger size, 

 very dark general coloration and particularly in the male supra- 

 anal plate, which in the present group is chitinous proximad and 

 laterad, the remaining portion occupied by an ample, soft, whit- 

 ish integument. 



Ischnoptera morio Burmeister (Plate XVII, figs. 1, 2, 3, 4 and 5.) 



1838. I[schnoptera] morio Burmeister, Handb. Ent., ii, abth. ii, pt. I, p. 

 500. [Colombia.] 



Burmeister's very inadequate description agrees with the 

 specimen before us. This insect is closely related to the new 

 species, I. atrata, under which the two are compared.*^ 



Characters of cf-— (Caracas, Venezuela.) Size very large for the genus; 

 form moderately slender. Interocular width three-fifths ocular depth, sub- 

 equal to interocellar width. Ocelh large, flattened surfaces of occUar areas 

 forming a sharp angle with interocellar area. Maxillary palpi rather short; 

 fourth joint slightly shorter than third, fifth (distal) joint distinctly the 

 longest and moderately enlarged, the ventral margin weakly convex from 

 the rather sharp apex to near the base where the convexity is more decided. 



•> We have not seen the female sex of morio. We feel that it will probably be 

 found to resemble that sex of the closely related alrata. 



