178 INSECT ARCHITECTURE. 



point touches the water; whilst the cocoon of leaves, 

 lined with silk, has been constructed underneath the 

 water. This fact proves that the caterpillar has a 

 particular art by which it repels the water from be- 

 tween the leaves. 



When a caterpillar, which has thus conveyed, and 

 disposed a patch of leaf against another leaf, is not 

 ready to be transformed into a chrysalis, it applies 

 itself to make a cocoon — a habitation which it may 

 carry everywhere about with it. It begins by slightly 

 fixing the piece against the whole leaf, leaving inter- 

 vals all round, between the piece and leaf, at which 

 it may project its head. The piece which it has 

 fixed serves as a model for cutting out a similar 

 piece in the other leaf The caterpillar puts them 

 accurately together, except at one end of the oval, 

 where an opening is left for the insect to project its 

 head through. When the caterpillar is inclined to 

 change its situation, it draws itself forward by means 

 of its scaly limbs rivetted upon the leaf The mem- 

 branous limbs which are rivetted against the inner 

 sides of the cocoon, oblige it to follow the anterior 

 part of the body, as it advances. The caterpillar, 

 also, puts its head out of the cocoon every time it 

 desires to qat. 



There is found on the common chick-weed ( Sfel- 

 laria media) towards the end of July, a middle-sized 

 smooth green caterpillar, having three brown spots 

 bordered with white on the back, and six legs and 

 ten pro-legs, whose architecture is worthy of obser- 

 vation. When it is about to go into chrysalis, to- 

 wards the beginning of August, it gnaws off, one by 

 one, a number of the leaves and sm.aller twigs of the 

 chick-weed, and adjusts them into an oval cocoon, 

 somewhat rough and unfinished, externally, but 

 smooth, uniform, and finely tapestried with white 

 silk within. Here it undergoes its transformations 



