FIELD BOOK OF INSECTS. 



from blackish, through brown and reddish, to yellowish. 

 The sand-colored species, with pale yellow and black hind 

 wings, so common on the shores of the Atlantic and of the 

 Great Lakes, is Trimerotropis maritima. In Arphia the 

 crest is not notched. In Psinidia (antennas of male longer 

 than the hind femora, basal joints strongly flattened; our 

 common species is fenestralis, whose black-bordered hind 

 wings vary from pale yellow to red), Trimerotropis, and 

 Circotettix (hind tibiae dusky towards base and at tip), the 

 crest is notched twice. Some of those with only one notch 

 are: 



1. Disk of hind wing nearly transparent, uncolored 2. 



Disk of hind wing opaque or colored 3. 



2. Pronotum roof-shaped and front margin angulate. 

 Chortophaga. Our common species is viridifasciata; it 

 may be either green or brown. 



Pronotum flat on top except for the prominent crest 

 which is higher in front than behind; front margin of 

 pronotum square-cut. Encoptoloplius. In sordidus the 

 base of the hind wings is yellow; hind tibiae with a pale 

 ring near the base. 



3. Body robust; lateral ridges of pronotum extending in 

 front of the principal groove and not cut by it. Hippiscus. 



Not so 4. 



4. Hind wings black with a pale border. . . .Dissosteira. 

 Hind wings yellow at base with a dark median band. 



Scirtetica marmorata (tegmina marbled with grayish and 

 dark blotches; hind femora dark at apex and with 3 dark 

 bands) and Spliaragemon (Plate XVIII). 



Acrididae with the pronotum not extend- 

 ing to near the tip of the abdomen but with 

 a prominent spine on the prosternum (the underside of 

 the first segment of the thorax) are grouped in this sub- 

 family. There are numerous species and even the common 

 ones cannot be satisfactorily differentiated without going 

 into technicalities. Scliistocerca americana (Plate XVIII) 

 is one of the largest in size and strongest in flight of our 

 grasshoppers; another species is called damnified, a name 

 which sounds good to him who chases these " Bird-locusts " 



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