LEPIDOPTERA. 
347 
This calculation, however, is invalidated, not only by the 
total omission of the families Bombycidm and CramhidcB, but 
from the author haying forgotten to eliminate from his calcula- 
tions the numerous Siberian and other exotic Lepidopiera enu- 
merated in Staudinger’s Catalogue. Nor is it probable that 
the fauna of Europe could be taken as a fair average of that of 
the whole world in the manner proposed by Keferstein. 
Girard has published (Ann. des Sci. Naturelles, Zool. 5© serie, 
tome xi. pp. 135-374) a lengthy paper on the temperature of 
the invertebrata, a considerable portion of which relates to Lepi- 
doptera. He considers the high temperature he has observed 
in the larva of Galleria cerella to be due to the nature of its 
food, and remarks on hibernation, the power of various insects 
to resist cold, questions the assertion of Nobili and Melloni that 
larvae always possess a higher temperature than perfect insects, 
and details all the most important experiments made by pre- 
vious observers as well as by himself, and fully describes the 
apparatus necessary for such investigations. In all cases the 
temperature in male Lepidoptcra is much higher than in tlie 
female. Tlie temperature of larva3 varies much, being some- 
times above and sometimes below that of the surrounding atmo- 
sphere. Smooth larvae, when about to change, are slightly 
warmer than the surrounding temperature, both externally and 
internally. But in hairy larvae, such as Bomhyx rubi, the in- 
ternal temperature is much higher, from the covering resisting 
the radiation of heat. Girard^s experiments on exposed pupae 
tend to show that their temperature gradually increases during 
their development. When pupae are withdrawn from the cocoon, 
their temperature is much higher than that of the surrounding 
air ; but if they are left exposed, soon sinks rapidly. It appears 
that the temperature of the bodies of larvae is equable, but that 
in flying insects that of the thorax is always much greater than 
that of the abdomen. Girard has always observed that the 
musky odour observable in convolvuli and ligustri [vide 
Cosmos, I860, tome xvii. p. 280) is peculiar to the males. It 
issues from the anus ; and he considers it to proceed from some 
accessory gland of the generative apparatus. He thinks that 
the male of Bombyx mori has a strong flight in the wild state, 
as Martins has reared some in the open air at Montpellier ; and 
in the third generation the males had already recovered the 
power of flight. In summing up, Girard notes a few points 
which still require investigation, states that he has confirmed 
the observations of Newport and Dutrochet, that the tempera- 
ture is always highest in the imago in insects with complete 
metamorphosis, and mentions the following observations of his 
own as new. In adult insects the temperature of the surface of 
the body never sinks below that of the surrounding air ; but it 
frequently does so in naked larvae, or in pupae removed from the 
