x] Beetles 113 
Chafers. 
The so-called white grubs are the larvae of chafer 
beetles. There are four kinds which are very destruc- 
tive to plant life: (1) Melolontha vulgaris, the common 
cockchafer or May bug; (2) Rhizotrogus solstitialis, 
the summer chafer or midsummer dor; (3) Phyllopertha 
horivola, the garden chafer or bracken clock ; (4) Cetonia 
aurata, the green rose chafer. 
These white grubs often do considerable damage 
to the roots of plants, causing many to die and others 
to look very sickly. Grass land is especially liable to 
attack and whole patches at times die off from the 
ravages of these grubs. This injury is sometimes 
attributed to wireworms. Young trees, turnips, cab- 
bages and other farm crops are also injured by attacks 
on their roots. In addition to the damage caused by 
the grubs, the beetles themselves feed on the leaves 
of various trees. The adults are easy to distinguish 
from one another. They are all characterized by 
having feelers ending in flattened or leaf-like structures 
folded one on top of the other. 
The cockchafer is the largest and usually measures 
more than an inch in length. The head and thorax 
are black, the wing cases brown, each case having 
five longitudinal smooth ridges. The whole body has 
a mealy appearance. Five of the abdominal segments 
have a white triangular marking on each side. The 
end of the antenna is composed of six leaves in the 
female and seven in the male (see Fig. 33a, 1). 
The summer chafer measures about 2 inch in length, 
is brownish in colour and covered with a quantity of 
rather long hairs. The markings on the abdomen are 
P.F. 8 
