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HEPIALUS ARGENTEOMACULATUS. 



By D. S. Kellicott, Columbus, Ohio. 



This beautiful uioth, described by Harris, is known to occur over a 

 rather wide range of the northern United States and Canada, and whilst 

 it is rather uucominou in local collections it must be an abuudaut insect, 

 at least in some localities ; one of these is in Oswego County, N. Y., where 

 I have found the larvse and pupa-shells in great numbers. Its habits 

 are quite in accordance with those of its congeners, so far as they are 

 known. It bores the roots and stems of the Speckled or Hoary Alder^ 

 Alnus incana. I have been unable to study the larval habits, except in 

 midsummer or in early spring, as it occurs in the section mentioned 

 above. At the former season the imagos for the year have escaped. 

 At the latter, the mature larvae are in galleries, often reaching far up 

 into the trunks, and the two broods, as I regard tbem, which are to ma- 

 ture in succeeding years are mostly in the uuderground portions. 



The larvcie of Cossidie and ^Egeriidte, which live in wood, appear to re- 

 quire more than one year to complete their growth. For example, that 

 of Cossus rohinicc requires three years, as the following experiment in- 

 dicates : July 1, 1882, eggs of this species were placed in a wound in 

 the bark of Rohinia pseudacacia. The tree selected was isolated and 

 there were no signs that its trunk had been attacked by borers. A part 

 of the eggs gave larva?, the castings of which were observed from time 

 to time at the place where the eggs were lodged. The latter part of 

 June, 1885, a female pupa shell of the Cossid was found at the same 

 place. Again I have shown, in a high degree of probability, that Har- 

 monia pini exists as a borer for three years {Ent. Americana, I, 171). 

 So this alder-boring species appears to pass a like period in the roots 

 and stems. I have already referred to the different broods found in 

 spring and summer. Again, I have had larva? under observation in 

 roots kept moist from July uutil the following May. They must have 

 been nearly two years old, but did not transform. The failure of the 

 original stumps, and the refusal of the larva? to make homes in fresh 

 ones, prevented further success. 



The life history appears to be as follows : The eggs are laid the first 

 week in June ; the caterpillars live for two years iu the roots; as the 

 third year advances they work upward more or less into the stems; iu 

 the spring of the third year they bore out to the surface, partially or 

 loosely plug the opening with chips, and transform ; there does not ap- 

 pear to be a well marked pupa cell, and it travels rapidly up and down 

 its tube for a long distance by means of the transverse abdominal teeth. 

 Pupation occurs about May 1, and moths emerge a month later iu the 

 locality cited above. The pupa shells have been found protruding from 

 trunks in a manner quite like those of other Cossids. 



