324 



INSECT ARCHITECTURE. 



process of building,— as is also done by the vapourer 

 (Orpyia antiqua, Hubner), and many others.* 



These are additional instances of the remarks we 

 formerly made, that caterpillars which spin a slight 

 web are transformed into perfect insects in a much 

 shorter period than those which spin more substantial 

 ones. Thus the cream-spot tiger (Arctia vilhca, 

 Stephens) lies in chrysalis only three weeks, and 

 therefore does not require a strong web. It is figured 

 below, along with another, which is still slighter, 

 though more ingeniously woven, being regularly 

 meshed like net-work. 



Cocoon of Arctia villica. 



Net-work cocoon. 



A very prettily-netted cocoon is constructed by the 

 grub of a very small grey weevil (Hypera Rumicis), 

 which is not uncommon in July, on the seed spikes 

 of docks (Rvmices). This cocoon is globular, and 

 not larger than a garden pea, though it appears to 



* See this figured in Insect Transformations, p. 



