Insects Bred from American Larch 77 
This cerambycid requires two years for the completion of 
its life history. As noted above, it was bred from material 
from two different sources. That derived from Crittenden 
consisted of the limbs of Tree I. This was confined during 
the entire summer of 1916 and during this time gave rise 
to only two borers, Polygraphus rufipennis and Eccopto- 
gaster picee. It was then removed to the laboratory Novem- 
ber 2, where the temperature conditions were such as to 
induce the larve to resume work. Adults of NV. longipes 
emerged January 30 and March 16. 
The second lot of material derived from Wanakena con- 
sisted of tops 2-4 inches in diameter of Tree IX, which 
had been blown down during May, 1916, and had become 
infested between that date and the middle of August. This 
material was confined in breeding cages outdoors till early 
in January, 1917, when it was brought into the laboratory, 
but was again removed to a cold room in the latter part of 
February, where it remained till June. It was then placed 
in an outdoor breeding cage, and on July 3, 11 and 18 
specimens of N. longipes emerged. Thus this form, which 
normally requires two years for the completion of its life 
history, was induced to emerge a season earlier by the treat- 
ment the material received. It should be noted in this con- 
nection that the specimens thus treated are slightly under- 
sized, measuring respectively 7, 8 and 8 mm., while those 
from the other lots of larch were from 9 to 9.5 mm., being 
entirely normal in size. 
NV. longipes deposits its eggs in larch which is either dying 
or recently dead. The larvee excavate deep, rather narrow 
burrows in the sapwood just under the bark. The larval 
mines are very long (Figs. 19, 20), in three cases where they 
could be accurately measured being 445 mm., 485 mm. 
and 568 mm. These measurements are rather too small than 
too large, as no attempt was made to measure the smaller 
curves in the course of the grooves. The entire burrow is 
packed full of rather fine frass by the larva, which, on becom- 
ing full grown, burrows into the wood to construct a pupation 
eavity (Figs. 19, 20). This chamber in the wood is also 
