THE LARGE LARCH SAWFLY. 49 
In answer to inquiries I give below Tables which may assist 
in making certain the determination of the large larch sawfly. 
Moru CATERPILLARS. 
Head somewhat hollowed out and 
not so globular. 
A group of ocelli on each side of the 
head. 
Hooklets on the abdominal legs. 
Legs 16 in number or less. 
The Geometer moth caterpillars, of 
which at least three species feed 
on larch, have a less number of 
legs than 16. The caterpillars 
of the larch mining moth (this 
was quite common in Cumber- 
land, and is often a_ serious 
enemy of the larch) mine into 
the needles, causing the upper 
half to shrivel up; these cater- 
pillars are very minute, and 
make cases for themselves in 
hollowed out parts of the needles. 
THE LARGE LARCH SAWFLY 
(Mematus Erichsonz). 
Adult 10 mm. in length, and with 
red on the abdomen. 
_ Thorax prominently and 
punctured. 
The eggs are laid on the young shoots. 
Caterpillar measures up to 22 mm., 
and is grey-green on the back, 
lighter on the sides. 
Head of caterpillar black. 
Caterpillars eat till the end of August. 
The caterpillar eats especially the 
leaf clusters or tufts. 
thickly 
SAWFLY CATERPILLARS. 
Head globular. 
One ocellus on each side of the head. 
No hooklets on the abdominal legs. 
Legs more than 16. 
Genus Lophyrus. Genus Mematus. 
é.g., the pine saw- 
flies, not found 
on larch. 
The caterpillars 
have 22 legs. 
The caterpillars 
have 20 legs. 
THE SMALL LarcH SAWFLY 
(NMematus laricés). 
Adult 6 mm. in length, and quite 
black. 
Thorax not prominently punctured, 
and may be quite smooth. 
The eggs are laid on the buds. 
Caterpillar measures up to 15 mm., and 
is grass-green or greenish-brown. 
Head of caterpillar brown. 
Caterpillars full grown in July. 
The caterpillar eats more commonly 
the single leaves on the shoot of 
the current year. 
Life-History and Habits of the Large Larch Sawfly—The 
caterpillars winter under cover of the cocoons, and pupate, 
generally speaking, in May or June, according to the conditions. 
I know of no records in Britain giving dates of the appearance 
of the adults, but probably they issue in June. The eggs are laid, 
in one or two rows, on the youngest larch shoots, and in slits in 
the bark made by the saws. Packard saw the eggs laid at the 
bases of the young leaves. (It will be recalled that on the new 
shoot, or shoot of the current year, in the larch the leaves are not 
in clusters but are arranged singly.) The presence of the eggs 
may cause the shoots to curl somewhat, and on occasion the 
leaf at whose base an egg has been laid, dies. Packard? 
1 Fifth Report of the United States Entomological Commission: ‘‘ Forest 
Insects,” 1890. 
VOL. 3, PART I. D 
