354 
Proceedings of Royal Society of Edinburgh. [sess. 
On 12th October 1898, for convenience I removed this pine from 
its tub and sawed it up into pieces, which were placed in a muslin 
bag, over which water was thrown at intervals. The spring of 
1899 passed without any issue of imago, but on dissecting in June 
I came across pupae in their beds, and so might soon expect escape. 
On opening the sack on 9th July 1899 (the sack not having been 
examined for some days) I found a number of P. pini had issued, 
and were crawling about the bag ; altogether twenty-nine had 
issued. 
By the end of the second week other 45. 
„ „ third „ 31. 
„ „ fourth „ 4. 
In August other 14 issued. 
Pine 2. 
On 29th July 1898 I placed thirteen pini on a thick piece of a 
freshly-felled full-grown Scots pine. This was to serve as breeding 
material, and in order to supply material on which the pini might 
feed and so continue to live, I enclosed in the same muslin sack 
a small three-year-old Scots pine. The pini were removed in this 
experiment on 30th August 1898. The thick log of freshly-cut 
pine was very freely used for egg-laying, and dissection after a 
time revealed feeding larvae. The first imago of the new brood 
issued on 24th July 1899. The beetles came away very rapidly. 
Before the end of July fifty had issued, and by the end of the 
first week of August other twenty-three. 
Pine 3. 
On 17th April 1899 I took five P. pini of the brood that had 
issued with one in the spring of 1897, and which had hibernated 
in 1897-1898, and placed them on a muslin enclosed pine. In 
the course of the summer breeding was attested by the presence of 
feeding larvae. The spring of 1899 was very cold, and this, I 
think, impeded development. The five pini were allowed to 
remain on the pine until 27th May, when they were removed. It 
