ON THE NORTH AMERICAN COSSID2. 5g 
were deposited singly and some in confused heaps, and were attached 
to each other and to the box with a viscid substance. 
Another female was captured June 20, and in forty-eight hours after 
being pinned she had deposited sixty eggs, which varied somewhat in 
color from the former, 
The Cossus after being pinned is very restive, especially while de- 
positing her ova and by the constant motion of the oviposter in endeay- 
oring to extrude the ova. The loove abdominal scales are removed and 
attached to the eggs by the moist viscid fluid with which they are cov- 
ered, and which often gives them the appearance of being clothed with 
scales. <A few of the ova collected this season have this appearance, 
but a strong lens exposes the true condition. C. centerensis is not so 
prolific as some of the other species of Cosside. C. robinie Peck and 
C. querciperda Fitch have been known to extrude upwards of three 
hundred ova. In European species over one thousand ova have beem 
found on dissection. The ruin of whole forests of timber in which these 
insects revel is doubtless prevented by the destruction of the eggs by 
ants and birds, the size of the eggs being sufficient to form a tempting 
morsel. In a state of nature the female Cossus deposits a small num- 
ber of her ova upon each tree which she visits until her supply is ex- 
hausted. 
This season the enlarged perforations through the bark show unmis- 
takable evidence that the trees had been recently visited by wood- 
peckers, which could find little difficulty in procuring an abundance of 
full-grown larvee. 
C. centerensis is found throughout the region known as the pine bar- 
rens, which cover an area of perhaps 12 square miles between Albany 
and Schenectady. The soil of this region seems especially well adapted 
to the growth of the timber which it supports. 
At the present time no correct observations have been made in ret- 
erence to the molts of the caterpillars, but information on this subject 
will soon be obtained from Mr. A. H. Mundt, of Illinois, who has had 
opportunities of observing, up to the fourth molt, the caterpillars of 
C. robinie, which are found in the willows and poplars in his vicinity. 
Cossus centerensis appears every year, and from observations and from 
numerous examinations of the trees by actual sections during the three 
months of the year enumerated, 1am convinced that the caterpillars 
are not fully matured until the end of the third year, when they arrive 
at their perfect or winged state. The pupa state is comparatively 
short, lasting less than a month before the moth appears. From figures 
3, 4, and 5 of Plate I we see representations of caterpillars found Octo- 
ber 14, which establish the fact beyond dispute, through observations 
extending over many years, that it requires three full years for the cat- 
erpillar to arrive at maturity. 
