PHVTOPHAGA CHRYSOMELIDAE 



283 



the epidermis; but when it has consumed about three-fourths of 

 the soft interior of the leaf it ruptures the epidermis of the upper 

 surface, and seeks another leaf; this found, it places itself on the 

 midrib, tears the upper epidermis, and lodges itself in the leaf 

 In the ease of this second leaf it attacks the parenchyma in the 

 neighbourhood of the petiole, and so forms an irregular tube 

 which has an open mouth, the point of entry. In this tube it 

 undergoes its metamorphosis. Each larva, it is said, always 

 makes use of two leaves, and of two opposed leaves. A know- 

 ledge of the habits of some of the larger' of the exotic Hispides 

 would be of much interest. 



Fig. 144. — Pupa of 

 Cassidid beetle 

 (? -4 spidom orpha 

 sp.). A, With 

 appendage ex- 

 tended ; B, with 

 the appendage re- 

 nosing on the back. 

 New Britain. 



The Cassidides, in addition to the curious marginal expansion 

 of their upper surface, have the power of withdrawing the head 

 into the thorax, and hence they are often called shield or tortoise- 

 beetles. They exhibit considerable variety in form and colour, 

 and some of them display a peculiar metallic reflection of great 

 delicacy and beauty ; this disappears entirely after death, but it 

 nray be restored by thoroughly moistening the dead Insect. The 

 colour, therefore, probably depends on the presence of water in 

 the integument. The larvae of Cassidides are notorious on 

 account of their habit of covering their bodies with dried 

 excrement, for which purpose they are provided with a forked 



