. The Cambridge natural history. Zoology. 322 LEPIDOPTERA transparent scale of somewhat inconstant ontline. Some are coloured and mottled somewhat after the fashion of birds'-eggs; this is the case with some eggs of Lasiocampidae and Liparidae ; in some the sculpture of the egg-shell is of the most elaborate char- acter (Figs. 77, 78, Vol. v.). The egg-shell or chorion is, accord- ing to Korschelt ^ and others, a cuticular product of the epithelium of the egg-chambers of the ovaries. Tlie number of eggs deposited by an individual differs greatly in different species, and has been ascertained t
. The Cambridge natural history. Zoology. 322 LEPIDOPTERA transparent scale of somewhat inconstant ontline. Some are coloured and mottled somewhat after the fashion of birds'-eggs; this is the case with some eggs of Lasiocampidae and Liparidae ; in some the sculpture of the egg-shell is of the most elaborate char- acter (Figs. 77, 78, Vol. v.). The egg-shell or chorion is, accord- ing to Korschelt ^ and others, a cuticular product of the epithelium of the egg-chambers of the ovaries. Tlie number of eggs deposited by an individual differs greatly in different species, and has been ascertained to be variable within certain limits in the same species. Speyer thought about 250 to be the average number of eggs deposited by an individual. The number in the case of Ajjuria crataegi is believed to be from 60 to 100, and in some Sepialus to be several thousands. The mode of deposition also differs greatly; where the eggs are very numerous they seem to be discharged almost at random in suitable spots; but moths such as Clisiocampa neustria fasten their eggs round the stems of the food-plant in a very perfect and artistic manner. Butterflies seem as a rule to prefer to oviposit by placing an egg here and there rather than risk many in one situation; but to this there are many conspicuous exceptions especially in the cases' where the larvae live gregariously, as in the Yanessae. Some moths cover the eggs with .^.-,,, fur from their own body, which, in the case of certain of the Eggers (Lasiocampidae), seems to have a special supply for the pur- pose. The period that intervenes between deposition and hatching of the eggs varies from a few days to many months. There seems to be, as a rule, comparatively little power of extending the period of latency beyond a single season ; though certain facts have been recorded that would lead us to believe that in Australia eggs may last over the proper time during a drought, and be hatched as soon as rain falls. Larva.—The young condition
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