8 FAUNA HAWAIIENSIS 



ACRIDIODEA. 

 OxYA Serv. 



(i) Oxya velox Fab. 



Oxya velox, Brunner P.Z.S. Dec. 1895, p. 893. 



Hab. Abundant on Kauai and Oahu, but had not spread to the other islands 

 in 1897. 



LOCUSTODEA. 



Elimaea Stal. 



(i) Elimaea appendiculata Brunn. 



Elimaea appendiculata, Brunner I.e. 



Hab. Very abundant throughout the islands, on the plains and lower slopes of 

 the mountains. 



Brachymetopa Redt. 



The ten species, which represent this genus, are closely allied to one another, 

 and for the most part very similar in general appearance. The genus, though peculiar 

 to these islands, is allied to the widely distributed Coiioccp/ialus, but still more closely 

 to the Hawaiian genus Conocephaloides, described hereafter. The latter indeed, with 

 the general appearance of a Conocephalus, combines the characters of that genus with 

 some of those which distinguish Brachymetopa from it. All the species of Brachy- 

 metopa have the tegmina and wings in a more or less rudimentary condition, and they 

 are useless for purposes of flight in either sex, but serve as stridulating organs in 

 the <J. In B. deplanata Z the tegmina are extremely short, being only as long as 

 the pronotum, but in some others they extend to the apex of the abdomen, while 

 in others again they are intermediate in length between these extremes. 



Several, and perhaps most, of the species have two distinct forms, a green and 

 a darker (or at least not green) one, which are so strikingly different as to suggest 

 at first sight that they are distinct species. There appear to be no really intermediate 

 forms, although the examples that are not green are themselves variable, the colour 

 varying from testaceous or ochreous to dark fuscous in some species. It is quite 

 possible that the two forms are really tending to become distinct species, at least 

 in certain cases, and the two Oahuan species B. discolor and B. blackbjcjnti may not 

 improbably have originated from a single simply dimorphic species. Certain it is that, 



