1877.] The Rocky Mountain Locust. 663 
THE ROCKY MOUNTAIN LOCUST? 
BY Oi Vi RILEY; PH.D. 
FE subject which you have assigned to me is entitled The 
Rocky Mountain Locust and the Army Worm. Both these 
insects are extremely injurious to the agriculture of the United 
States, and as it would be difficult to do justice to both in the 
compass of a brief address I shall confine my remarks at the 
present time to the first named. So much has been written and 
said, by myself and others, upon this Rocky Mountain locust dur- 
ing the past two or three years that it would seem difficult in- 
deed to say anything about it that is new or of value. Yet I 
may safely assert that most of the definite and accurate knowl- 
edge regarding its habits and life history was first given to the 
world during the present year. 
Though popularly known as the “ grasshopper,” yet the term 
“ Rocky Mountain locust,” proposed by myself, has been very 
generally adopted as most appropriate. The insect belongs to 
the same family as the locusts of Scripture. The term grass- 
hopper is very loosely applied to many insects that hop about 
in grass, but strictly belongs to the long-legged, long-feelered 
Species. Locusts have short and stout legs, short and stout 
feelers, and are mute, or, if they stridulate at all, do so by rub- 
bing the hind thighs against the sides of the folded front wings ; 
their prevailing color is brown; they are gregarious, and they 
Oviposit in the ground by means of short, drilling valves. True 
grasshoppers have long and slender legs and feelers, and stridu- 
late by vibrating the front wings, which in the males are fur- 
nished, generally near the base, with tale-like plates crossed by 
enlarged and hollow veins; their prevailing color is green ; they 
are solitary, and they mostly oviposit in different parts of plants, 
by means either of a sword- or scimeter-shaped ovipositor. It is 
the grasshoppers, the katydids (which are a tree-inhabiting sec- 
tion of them), and the crickets which make field and wood resound 
_ With shrill orchestry at the present season ; but the locusts take no 
part in the concert. While our insect belongs, therefore, to the 
Same family as the locusts of Scripture, those people are greatly 
at sea who imagine it to be specifically identical with any of the 
Asiatic or European species. It is known to entomologists as 
1 An address delivered at the Chicago session of the American Agricultural Con- 
Stess, in September, 1877. Some portions are omitted for want of space. — Ep. 
