384 FIFTH REPORT OF THE ENTOMOLOGICAL COMMISSION. 
t;. The sixtkeh-leggko mai'lk-uoker. 
.]■'.<!< via actnii (Clemens). 
Order Lkpidoptera.; family JEQKSOADM. 
Following the work of the flat-beaded borer, harrowing under the bark of the soft 
maple, sometimes girdling and killing the tree, a caterpillar with sixteen legs, spin- 
ning a cocoon of silk covered with its eastings; the moths issuing from the tree late 
in May and thence through the summer, the worms occurring under the bark through 
the summer and winter. (Riley.) 
This borer is sometimes very destructive to soft and sometimes to 
sugar maples, especially young trees, in Ohio, Illinois, and Missouri, 
the moths sometimes emerging in great numbers from the trunks of the 
trees in May and June. Mr. G. K. Pilate states that the red maple trees 
in Dayton, Ohio, were greatly infested by this borer, in consequence of 
which a large number of those shade trees are dead or dying. (Bull. 
Brooklyn Ent. Club, vol. i, 20.) 
Mr. Kellicott remarked in the Canadian Entomologist for January, 
1881, that the u larvre of this moth are annually doing much damage 
to the hard maples (Acer saccharinum), 
planted so generally in this city [Buffalo] 
for shade ; they are less destructive to the 
soft maple (A. rubrum). It appears that 
they seldom attack uninjured trees, but 
depend upon accidents to afford them op- 
portunity to enter the inner bark and su- 
perficial wood ; when once established they 
keep at the scar or wound year after year, 
thus preventing recovery and causing the 
trunks to become rough and unsightly ; in 
many cases the trees are thus almost 
ruined. The moths appear most numer- 
ously from May 20 to June 15. I have 
not been able to find, after patient search, 
this borer in our forest maples." 
Professor Riley says he has always found 
the worms in such trees as have been in- 
jured either by the work of the flat-headed 
borer, by the rubbing of the trees against 
a post or board or in some other way. " Where the bark is kept 
smooth they never seem to trouble it, the parent evidently preferring 
to consign lier eggs to cracked or roughened parts. For this reason the 
worm is not found in the smoother branches, but solely in the main 
trunk." 
Remedies.—" Whether the soap applications will prevent the moth 
from depositing her eggs is not known ; judging from analogy, probably 
not. Yet it will tend to keep the bark smoother, and in being used to 
FlO. 142. — c, JBgeria acerni . a. cater- 
pillar; b, cocoon ; (/, pupa cases. — 
After Riley. 
