244 PITYOGENES CONIFER&, MS. 

Relations to the Forest. 
This little beetle con fines its operations to the smaller branches 
of the Blue pine! where the bark is still quite soft. It infests 
these places in enormous numbers, working in company with the 
larger Polygraphus. Itis to be found in the side branches 
and upper portion of the leading shoot of older saplings. 
In smaller ones it infests every part and it then becomes a 
serious pest, as it would appear to have the power of increasing 
in large numbers. In the case of the snow-broken Blue 
pine saplings alluded to as attacked by the larger Polygra- 
phus (see p. 236 ante), this beetle was in countless numbers 
wallowing in the large amount of turpentine contained in the 
more succulent portions of the young trees, Its attack can be 
recognized from the outside by the small pin-holes seen in the 
bark, each surrounded with a small white ring of resin (see Pl. 
XIII, fig. 4, f(n)); the bark when very young turns yellow 
under the attack and shrivels up. The arms of the stellate 
galleries run longitudinally up and down the stem rather 
than horizontally, and the appearance of the pairing chamber 

1 [| have since found it in company with Polygraphus major infesting 
deodar saplings. It was very numerous in the tops of saplings already 
described as attacked by its larger companion at Pajidhar (see footnote 
on p. 237). In a few cases it was found in the main stem, low down, 
and the gallery had then only 4 arms or egg galleries to it, the pairing 
chamber being made entirely in the bast as also were the jiarval 
galleries and pupating chamber, only the egg galleries grooving down 
into the sapwood. In the tops, however, and leading shoots the attack 
corresponded in all respects to that in the blue pine. I was unable to 
count the number of egg galleries bored as the bark and sapwood were 
riddled by the interlacing galleries. All the stages of larva, pupa and 
beetle, were found, and also mature beetles just boring into the stems to lay 
eggs. This would seem to confirm my theory that the generations in one 
year ofthe life history of this insect overlap one another since it would 
seem probable that the larvee were those of the second generation, the first 
lot of grubs appearing somewhere about the beginning of May. This would 
mean that the August-September larve are those of the third generation, 
and the November beetles those probably of a fourth which lay the eggs of 
the first at the end of April in the following year. The Pityogenes was 
equally numerous in the neighbouring blue pine saplings. As in the case 
of the P. major the fact that this beetle attacks the deodarin addition to the 
blue pine greatly adds to the importance of the pest and renders it essential 
that its life history should be understood. 
2 
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