Botany and Zoology. 419 
important than the sexual sculpture of the abdomen, the ultimate 
neuration of the tegmina, the length of the legs, the contour of the 
trochanters, or the digitation of the tibiw, which separate Scapter- 
iseus and Gryilotalpa. 
_ The facts cited above present two features which bear upon the 
question of the origin of species. 
_ First: these little mole crickets, so unique in their structure as 
to be widely separated from their nearest allies, are spread uniform- 
_ lyover the whole surface of the globe; but few species occur in 
_ any one place, and at least one is found in every temperate or hot 
abiiat, this same unique structural form has sprung up all over. 
o 
the globe? 
ca, from some previous synthetic form of mole cricket, both 
sent fe 
of the world the four-fingvered speci ly—destroying at the same 
é d o pecies only: ying 
time the primeval form : 
d ‘With distant nervures, simple and slight divarications, an 
the outer half of the wing, which alone is preserved, @ CTOs 
