13 



information that they had been sent him from Harristown by a 

 farmer, who reported that they were doing serious damage to the 

 roots of his young corn. On the '22d of that month they were again 

 sent me, by Mr. E. H. Mills, of Dwight, in Livingston county, with 

 the following note : 



"My corn is being badly damaged by small worms. I send you 

 specimens of them, all of which were found in one hill. There are 

 usually not more than three or four in a hill. The corn is large 

 enough so that we are cultivating it. I shall be very glad if you 

 can give me some information in regard to the worms. They are 

 making bad work with the corn in our fields." 



On the 23d, Mr. D. C. Tomlinson, of Osco, Henry county, sent 

 me other specimens of the name species, from a field of corn on 

 clover and timothy sod, which had been plowed up early in April. 

 His whole held had been so completely destroyed by this larva, in 

 conjunction with two species of cutworms, as to necessitate replant- 

 ing. He found the new larvae (now three-eighths to se.ven-eighths of 

 an inch long,) partly or wholly encased in a web within the ground. 



On the 27th May, I visited Dwight for the purpose of searching 

 the fields of Mr. Mills from which the web worms had been sent 

 me. The corn in this field was injured most in patches. Over one 

 area of about one-fourth of an acre, many hills were missing, and 

 fully one-third of those remaining were damaged, with a plant occa- 

 sionally killed. Upon digging into the affected hills, the caterpillars 

 were found just beneath the surface, sometimes as many as five or 

 six in a hill, each in a retreat formed by loosely webbing together 

 a mass of dirt irregularly cylindrical in shape, one and one-half to 

 two inches long, and about one-half an inch in diameter. The 

 worm was found in a silk-lined tube wdthin this mass (the tube not 

 always perfectly constructed), which in some cases opened at the 

 surface, its presence being indicated by a circular opening about the 

 size of wheat straw, in the earth next a stalk of corn. 



The first attack upon the plant was made by gnawing the outer 

 surface beneath the ground and above the roots. Occasionally the 

 stalk was completely severed, as by a cutworm, but usually not, the 

 larvse showing rather a disposition to work upwards, eating a super- 

 ficial furrow or burrowing lengthwise along the center of the stem. 

 In other parts of the field, only here and there a stalk was attacked. 

 The foliage was also frequently eaten, the lower leaf first and then 

 the upper ones, the larva evidently leaving its burrow for this pur- 

 pose. The tips of the leaves were eaten off, or irregular elongate 

 holes were eaten through them, — probably at night, as I have never 

 seen the larva abroad by day. Where the corn was largest, webbed 

 masses of dirt were frequently found which contained no larvse, a 

 fact which 1 was at first inclined to suppose indicated that the in- 

 sect inhabiting them had transformed, especially as the larvne found 

 were of quite uniform size and apparently full grown. I failed to 

 find a single pupa, however; and as our breeding experiments did 

 not yield the insect for more than a month, it seems more likely 

 that these empty webs had been abandoned by worms which had 

 gone in search of younger stalks. 



