58 PROCEEDINGS OF THE ACADEMY OF [March, 



The diagnostic features given by Scudder in the key of his study 

 of the genus are largely valueless, extensive series exhibiting clearly 

 their variability. In a few cases their importance is relative, 

 but not primary. 



Morphological Variational Notes. — Probably the most striking 

 feature of variation in the external morphology of the species of 

 this genus is in the form of the fasti gium, when viewed from the 

 dorsum. Practically the only satisfactory method of comparison 

 in the variation of this feature is to measure the angle, and the 

 extremes have been figured and discussed under each species. 

 The folly of using a feature of this sort in a strictly diagnostic 

 sense is evident when it is known that certain species show varia- 

 tions of from 33° to 65° (alacris), 52° to 84° (inter texta) , and 62° to 

 87° {maculipennis maculipennis and mac. macclungi) in the male 

 sex, and 42° to 70°, 80° to 95°, and 65° to 95° respectively in the 

 female sex. In addition to the exact angle there is much varia- 

 tion in the curvature or relative straightness of the margins them- 

 selves. The facial line shows occasional variation from the specific 

 type, but these are generally geographic. The frontal costa varies 

 much in its degree of sul cation and also in exact form, so much 

 so that we prefer to dispense with it as a diagnostic feature. The 

 form of the frontal costa, its exact width and relative depth are 

 so variable that no great weight can be attached to these features. 

 As we have already mentioned under "Classification," there is 

 a very considerable amount of variation in the form of the caudal 

 femora. Those species having the more slender type of caudal 

 femora show less of such variation than the species having nor- 

 mally more robust and less attenuate femora. 



There is a considerable amount of geographic variation in pro- 

 portions and form, this being particularly apparent in southern 

 Arizona material of 7naculipennis and neo-mexicana. In size, in 

 addition, there is a very decided amount of geographic variation, 

 the details of which are given under the individual species. 



Color Pattern. — The basic color pattern of the genus is found 

 in all the species, i. e. a pale base color, of a green, greenish- yellow, 

 brownish or ochraceous tone, with a pair of dark postocular bars 

 extending across the postocular portion of the head, the dorsal 

 section of the lateral lobes of the pronotum, thence spreading 

 out and to a greater or lesser degree continued as a narrow line 

 on the pleura, and intensively coloring the marginal and discoidal 

 fields of the tegmina. In addition there is frequently a medio- 



