SPINNIXG CATERPILLARS. 283 



meiiy 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 villica, Stephens) lies in chrysalis 

 only three weeks, and therefore does not require a strong 

 web. It is figured in the preceding page, along with 

 another, which is still slighter, though more ingeniously 

 woven, being regularl}^ meshed like net-work. 



A very prettily-netted cocoon is constructed by the grub 

 of a very small grey weevil (Hi/pera Rumicis), which is not 

 uncommon in July, on the seed spikes of docks (liumices). 

 This cocoon is globular, and not larger than a garden pea, 

 though it appears to be very large in proportion to the 

 pupa of the insect, reminding us not a little of the carved 

 ivory balls from China. The meshes of the net- work are 

 also large, but the materials are strong and of a waxy con- 

 sistence. Upon remarking that no netting was ever spun 

 over the part of the plant to which the cocoon was attached, 

 we endeavoured to make them spin cocoons perfectly 

 globular, by detaching them when nearly finished ; but 

 though we tried four or five in this way, we could not 

 make them add a single mesh after removal, all of them 

 making their escape through the opening, and refusing to 

 re-enter in order to complete their structure. (J. E.) 



The silk, if it may be so termed, spun by many species 

 of larvae is of a still stronger texture than the waxy silk of 

 the little weevil just mentioned. We recently met with a 

 remarkable instance of this at Lee, in the cocoons of one of 

 the larger ichneumons {^Ophion Vinulce? Stephens), inclosed 

 in that of a puss-moth ( Cerura Vinuld) — itself remarkable for 

 being composed of sand as well as wood, the fibres of which 

 had been scooped out of the under-ground cross-bar of an 

 old paling, to which it was attached. But the most singular 

 portion of this was the junction of the outer wall with the 

 edges of the hollow thus scooped out, which was formed of 

 fibres of wood placed across the fibres of the bar nearly at 

 right angles, and strongly cemented together, as if to form 

 a secure foundation for the building. 



In this nest were formed, surreptitiously introduced into 



