﻿OF THE STATE ENTOMOLOGIST. 



323; 



Indeed, since the Yilfa ripens and dies early in the Fall, the blue 

 grass gains ground the very first. year, and afterward easily retains 

 supremacy. The wide-spread appearance of the Vilfa, following the 

 locusts, has been explained on the hypothesis that the latter brought 

 the seed from the West and passed it undigested with their droppings. 

 The fact that the seed is a line long, and not particularly hard, aside 

 from the other facts in the case, renders such a hypothesis unreason- 

 able. Being an annual, the seed was scattered the previous Fall, and 

 naturally starting, we may presume, about the time the insects left,, 

 the species got the ascendency. 



Some persons were quite alarmed at the prevalence of large green 

 and black worms, soon after the locusts left. Feeding upon purslane 

 and prevailing to an unusual degree, because of the unusual preva- 

 lence of this plant, they generally did good by keeping this weed 

 down and converting it into manure. In some few instances, how- 

 ever, they swarmed to such an extent as to devour all the purslane^ 

 when they attacked grape-vines, and as Mr, Thos. Wells, of Manhat- 

 tan, Kansas, informs me, even cut off corn when it was about a foot 

 high. These worms were the variable larvse of the White-lined 

 Morning Sphinx, a pretty moth often seen hovering over flowers at 

 evening. The species was treated of in my third Report (p. 140) and 

 the illustrations are herewith reproduced. Most insects that naturally 

 feed in Spring above ground on low vegetation were killed out, and 



the only species un- 

 affected by the visi- 

 tation were thos©^ 

 feeding on forest 

 trees, or living in 

 the ground or in the 

 trunks of trees. The 

 White-lined Morn- 

 ing Sphinx, was just 

 issuing from the 

 pupa, which had re- 

 WMte-iiuedMommg Sphinx. maiued uudisturbed 



below ground, when the locusts were leaving. It found the purslane — 

 its favorite food-plant — everywhere springing up and abundant, and 

 its eggs were laid without diflficulty, and the young larvns did not, in 

 any case, lack for food. As a consequence they prevailed to a remark- 

 able degree. 



