40 GUIDE TO ORTHOPTERA 



d 1 . Hind tibiae armed on exterior margin with at least 

 nine spines *...... Melanopli. 



d 2 . Hind tibiae with six to eight spines only on the 

 exterior margin. Dactyloti. 



Tropidonoti. 



Our only representative of this group is the genus Dracotettix 

 Bruner, with a superficial resemblance to the Pyrgomorphinae, 

 and of which two species occur in the southern portion of our 

 Pacific coast in California and Arizona. 



Taeniopodae. 



Dictyophorus Thunberg is our only genus, the two known 

 species of which occur in our extreme southern states. 



RJiomaleae. 



A single species of Rhomalea Burmeister, a tropical genus, 

 occurs in Texas. 



Tropidacres. 



Of the gigantic forms in this group, Tropidacris Scudder is the 

 only one which extends north into our territory; a single species 

 is found in Texas and has even been reported as far north as 

 Nebraska. 



Mesopes. 



Our only representative of this small group is Pseudopomala 

 Morse, with two or three species in the northern half of our 

 country east of the Rocky Mountains. 



Leptysmae. 



This is an American group, consisting of only two genera, dis- 

 tinguished below. 



* There are occasional individual exceptions to this, where, as by accident as it 

 were, only eight spines are present on one or both tibiae. 



