54 REPORT ON INJURIOUS INSECTS FOR 1905. 



should be poured out quickly in order not to inhale the fumes- 

 there is no danger in inhaling a small quantity and the bin closed 

 and kept shut for at least five hours, after which time it should be 

 well ventilated, as also the fumigated goods. 



APPENDIX B. 



For the benefit of those possessing no special knowledge of 

 Entomology, it may be well to point out that, with a few excep- 

 tions, all insects are hatched from eggs. From the eggs the larvae 

 or caterpillars hatch out, and after a time these change into pupae 

 or chrysalides, each ultimately developing into an imago. 



The Eggs. These are exceedingly variable in shape, size, and 

 colour They may be laid singly or in groups. Sometimes they 

 are protected.by a gummy secretion, whilst others are fastened by a 

 short thread. The food of the young in nearly all cases determines 

 the place where the eggs are deposited, such, for instance, as on 

 leaves, close to or in roots, in blossom buds, beneath the bark of 

 trees, on cattle, meat or decaying animal or vegetable matter. The 

 number of eggs laid by a single insect may be very few or many 

 thousands ; fifty to a hundred, however, may be taken as an average. 

 The period of hatching, generally speaking, is not of long duration, 

 though there are cases where they remain unhatched for a con- 

 siderable length of time. 



The Larva. In a few cases this is produced alive, but usually 

 it is hatched from an egg. The larvae of Butterflies, Moths, and 

 Sawflies are commonly spoken of as caterpillars, those of Beetles 

 as grubs, while those of Flies are known as maggots. 



If a larva possesses legs, the first three segments behind the 

 head each carry a pair, which are jointed and known as thoracic 

 or true legs. Legs may also be present on the posterior segments, 

 but these are never jointed; they are known as pseudopods or 

 prole gs. 



It is often very difficult to say exactly to what particular order 

 a larva belongs, but, speaking in general terms, we may say that 

 the larvae of Butterflies and Moths exhibit the following char- 

 acters : A well-defined head provided with biting jaws : a pair of 

 jointed limbs on each of the first three segments behind the head, 

 a pair of pseudopods on the sixth, seventh, eighth and ninth seg- 

 ments, and sometimes a pair of larger anal feet on the twelfth 

 segment, making a total of sixteen. The " Looper " caterpillars 

 have pseudopods on the ninth and twelfth segments only, making 

 a total of ten. The caterpillars of a few months are footless. 



The larvae of Beetles possess a well-defined head and biting 

 jaws, and a pair of jointed legs on the first three segments behind 

 the head (Rose Chafer) or legs are entirely absent (Garden Weevil). 



The larvae of Flies (Diptera) are generally legless and usually 

 the head is merged into the thorax ; some, however, possess pseudo- 

 pods and a head. 



