116 Beetles [cu. 
are easily distinguished by the red spots which the latter 
possesses on each side of the segment behind the head. 
When full grown those of the summer chafer measure 
over an inch in length, whereas those of the garden 
chafer only measure 3 inch. 
The life histories of these beetles differ chiefly in 
the length of time from one generation to the next. 
The cockchafer takes four years to complete its life cycle 
in this country, but in some countries it may take three 
or five. The length of life of the summer chafer is 
not known with certainty, but is thought to be either 
one or two years. The garden chafer has a new genera- 
tion every year. The green rose chafer has a new 
brood every two or three years. 
Cockchafers make their appearance in May and are 
often abundant for five or six weeks. They remain 
concealed during the day and fly about after dusk. 
The leaves of oak trees are their favourite diet. The 
female burrows into the earth to lay her eggs, pre- 
ferably in loose soil or grass land, and lays about 
ten eggs. The grubs hatch from these in about 
six weeks. During the first summer they do very 
little damage as decaying matter is their chief food. 
In the following years they feed on plant roots. In 
winter they escape the unfavourable conditions by 
going deeper into the soil. After spending three years 
in the grub stage they scoop out recesses deep down in 
the soil and change into pupae. The beetles come up 
in the following May. The cockchafer grubs are 
responsible for most of the damage done to young 
trees. Young oaks and conifers suffer considerably. 
The life history of the summer chafer is very 
similar, the beetles appearing after the cockchafers in 
