164 Second Report on Economic Zoology. 
Life-history. 
The adult beetles hibernate during the winter in the following 
places : — 
(1) Under old stones and loose willow bark ; (2) amongst the 
leaves, rubbish, etc., collected in the old willow stumps ; (3) on the 
ground amongst fallen leaves ; (4) amongst the heaps of osier peel ; 
(5) in the hollow stem of herbaceous plants; (6) amongst the 
rubbish brought by winter floods ; (7) amongst the thatch of willow 
peelings used for huts in osier beds, etc. ; (8) between boards that 
overlap of any shed or building near ; and (9) amongst the terminal 
shoots of young pine trees. 
From these shelters they emerge in spring and lay their eggs 
in small groups on the under surface of the leaves. The eggs are 
grey and spindle-shaped, and are covered with a thin irregular 
transparent coating. From these eggs the larvae hatch in a few 
days and at once commence to eat away the lower layers of the 
leaves. They feed together in irregular rows as a rule, but now and 
then isolated specimens may be found. The larva is dirty yellow 
in colour ; when full grown they reach half an inch in length, with 
four prominent brown spots on each segment dorsally, the head and 
legs deep brown ; they resemble somewhat in form the larvae of 
lady-birds, being enlarged anteriorly and narrowed posteriorly. The 
brown spots vary somewhat, and in addition to those on the back 
there are lateral ones, and on the last two segments a squarish black 
mark. The markings of the three thoracic segments are the most 
pronounced. When mature they drop to the ground and pupate in 
the soil. From these pupae the beetles hatch out in the autumn and 
feed upon the leaves as long as they can get any sustenance and 
then hibernate in the places previously mentioned. 
Protective and Remedial Measures. 
(1) As far as possible all such places as mentioned as winter 
quarters should be removed or done away with during winter. Huts, 
etc., in and around osier beds should be built with due regard to 
the fact that beetles hibernate there. The use of osier peelings for 
roofing should be abolished. 
(2) Traps may be laid towards the end of summer to draw away 
the beetles ; birch bark, planks or the peelings may be put in heaps 
above flood level and burnt during the winter together with the 
beetles collected in the traps. 
(3) Flood refuse should be burnt before spring. 
