HARMFUL INSECTS 139 
The following details should be carefully noted. 
(a) Food-plant of larva. 
(b) Number of days between each moulting. 
(c) Changes which larva undergoes. 
(2) Habits of larva e.g. whether a day or night feeder. 
(ce) Formation and description of cocoon. 
(f) Number of days between first appearance of larva 
from egg and formation of cocoon. 
(g) Duration of pupa stage. 
NotEr.—The only real way for children to understand insect life 
is to follow the life history of a few forms through the various 
stages of development. Butterflies and Moths are the best 
subjects to work with ; and the eggs of the Silk Worm Moth, as also 
those of the commoner Butterflies are not difficult to obtain. These 
eggs should be placed in suitable boxes an d the changes they 
undergo in the development of the perfect insect carefully noted. 
Pupils should be allowed to bring the food required and taught the 
necessity of regularly attending to the wants of the animals. A 
careful record in accordance with some such plan as that suggested 
at the end of the chapter should in all cases be kept. 
There is no reason why a beginning should not be made in the 
Infant Department, where the initial stages might be devoted either 
to examining the structure of the insect, or to developing a few 
forms. If the former course be adopted, large diagrams are a 
necessity, as many of the insects most readily available, e.g Bee and 
Silkworm Moth, are so small that pupils have much difficulty in 
examining them. It is not to be supposed however that this 
advocates doing without the insects themselves ; these in some form 
must always be available, but no lesson can be considered complete 
in which diagrams and blackboard drawings are not utilized. 
It has often be urged that a study of insect-life should be deferred 
until towards the close of the nature-study course. This contention 
has much to recommend it, for the creatures themselves are so 
small that there is difficulty in observing characteristic details, and, 
besides, there are many other forms of life in which little children 
are more interested. Still a good deal of useful work in the Infant 
Department can be done in the direction indicated ; though as in 
other phases of the subject much will depend on the tastes and 
knowledge-equipment of the teacher. In the upper classes special 
