l60 TRANSFORMATIONS OF INSECTS. 



the rudiments of a mouth are found, and of two eyes without facets. 

 The movements of these admirable examples of retrograde meta- 

 morphosis — and how slightly they resemble the well -developed 

 Lcpidoptcra ! — are extremely sluggish, and the six little feet of the 

 thoracic segments, which are in the form of very short conical 

 processes, scarcely take any part in them. A dissection proved 

 these moths to be true females. They deposited their yellowish 

 eggs in the empty pupa case which in Psyche always remains 

 behind in the caterpillar sac ; they then shrivelled up to a very 

 small volume, when they generally left the sac by the above- 

 mentioned side aperture, and soon afterwards died." Von Siebold 

 proceeds in the description of this strange case as follows : — " The 

 unfertilised eggs concealed in the pupa case are also developed in 

 the same year. If a spun-down sac of PsycJie helix be opened in 

 the latter part of the autumn, or in winter, we always find from ten 

 to twenty-four young reddish-grey caterpillars in the interior of the 

 pupa case." No other method of reproduction but by virgin 

 females, and without the influence of the male, was witnessed in 

 this Psyche by Von Siebold. 



Heroldt described the changes which go on in the young silk- 

 worm within the eggs laid by unfertilised female moths, and found 

 that development proceeded all the same ; and Von Siebold 

 acknowledges that the silkworm can be raised occasionally from 

 unfecundated eggs. 



Other observers have decided that the tiger and other moths 

 can be thus reproduced, but the above instances must suffice to 

 show the extraordinary method of reproduction amongst the 

 Lcpidoptera, which is of such great importance amongst the bee 

 tribe. 



The alterations in the external structures of some genera 

 during successive moultings of the skin have been pointed out. 

 Thus in Hadcna oleracea, the caterpillar has different colours 

 when old to those which ornamented it during the early part 

 of its life, and the " Forked Tail " undergoes alterations in 

 colour during the skin casting process. Attacus cccropice submits 

 to corresponding changes in its tints. It is thus necessary to 

 consider the moulting periods as most important epochs in the 

 evolution of the Lepidoptcra, although the marked stages of meta- 



