Annual Report fur 1894 of the Zoologist. 
777 
willow, mountain ash, beech, and hornbeam. After pairing, the 
female seeks suitable ground for laying her eggs, and for this 
purpose comes out into the open. The ground preferred is untilled, 
tolerably loose, and dry, and the eggs are laid at a depth of about 
10 inches. In all, each insect lays sixty or seventy egg's, about 
fifteen at a time. 
In four to six weeks the larvie hatch out, but during the first 
summer they do little harm, feeding for the most part upon decaying 
vegetable matter in the soil. During the following year they begin 
to attack the tender rootlets of various crops, and enter definitely 
upon their career of destruction. In winter they avoid the severe 
frosts and get beyond the reach of the agriculturist by burrowing 
very deeply in the ground. They are whitish, fleshy, wrinkled, 
grubs with yellow heads, and of the shape figured above. 
The duration of larval life is probably three years. Pupation 
then takes place in J uly or August, and in the following May the 
mature beetle appears. 
On the Continent the life-cycle is found to occupy three or four 
years, according to the climate. The period is four years in North 
Germany, three years in South Germariy and in Switzerland. These 
periods are emphasised by the appearance every third or fourth year, 
as the case may be, of swarms of cockchafers, very much more 
numerous than those observed in the intervening years, and such 
“ swarming-years ” (Flugjahre) are, of course, known in advance, 
and special means taken to destroy the beetles. In Dresden, for 
example, the swarming years correspond with the leap-years, while 
in other districts they may fall on the years preceding or the years 
following leap-years. 
It is very important that information of this nature should be 
obtained with regard to infested districts in the British Islands. 
From the size of the larvae sent me this year from Godaiming 
and from Glamorganshire, I should judge that the present year 
is a “swarm-year” for those districts; but I have no information 
as to the numbers in which the cockchafer occurred there last 
May. The grubs received from Ross-shire in September appeared 
to be of two years’ growth, and would indicate 1893 as a “swarm- 
year.” 
The slight damage done by the grubs in their first year often 
induces the farmer to think that he has got rid of the pest. 
Quantities of the young grubs were found this year in Surrey and 
in Glamorganshire at the roots of flourishing grass- crops. 
Treatment . — When it is considered that in this country grass- 
crops principally suffer from the cockchafer, it is clear that the 
usual methods of grub destruction during tillage operations are 
not available. It is in the beetle stage that the pest is most subject 
to attack, and hence the importance of accurate observations in the 
directions indicated above. 
In infested districts farmers should act in concert in attempting 
to destroy the beetles wholesale during May. The insects never 
travel far to lay their eggs, so that a district is benefited by the 
