JAMES A. G. REHN AND MORGAN HEBARD 317 



margins and the extent and character of the armament of the 

 same. 



The North American species of the genus Amhhjcorypha fall 

 quite naturally into two groups. Group I contains six forms of 

 varying size, all having an elongate form with markedly elongate 

 tegmina and distinctly projecting wing tips, individually sul)- 

 equal or longitudinal metasternal lobes, and a well marked humeral 

 sinus. Certain features, as the form of the distal margin of the 

 subgenital plate of the male and the character of the ovipositor 

 margins, are of diagnostic value within the group, while the promi- 

 nence of the lateral angles of the pronotal disk and the extent 

 of the same show within the group the extremes of variation for 

 the genus. 



In the assemblage comprising group I certain affinities are 

 evident Vv'hich a linear arrangement camiot express. On the 

 one hand oblongifolia and on the other ^ihleri are very distinct 

 and isolated types, while the floridana-huasteca-insolita division 

 is more homogeneous. Insolita is a desert representative of the 

 huasteca type, while floridana carinata is distinctlj^ divergent 

 from floridana floridana in the direction of oblongifolia, to which, 

 however, it is no way closely related. Huasteca and floridana 

 floridana show quite a few features in common, but the differ- 

 ences in form of the ovipositor and of the male subgenital plate, 

 as well as in the general shape of the stridulating field of the male 

 tegmina prove their relationship to be by no means as close as 

 would appear at first glance. 



Forms of Group I 



[ ohlongifolia 

 floridana floridana 

 Forms of large size, slender build. \ floridana carinata 



huasteca 

 ^ insolita 

 Forms of small size, slender build, uhleri 



Group II contains three forms which arc all closely related and 

 undou])tedly geographic races of the same species, for which the 

 name of the first knowni form — rotnndifolia — must be used. These 

 are all of medium size, modcn-ately or decidedly abbreviate form, 

 with ovate tegmina, slightlj' or not at all projecting wing tips, 



TRANS. AM. ENT. SOC. XL. (23) 



