POx^DWEED TENT-MAKER. 155 



(^Hydrocampa potamoget(i) was lodged. An indefatigable ob- 

 server, such as M. Eeaumur, would naturally follow up 

 this discovery ; and he has accordingly given us a memoir 

 of the pond weed tent-maker, distinguished by his usual 

 minute accuracy. 



In order to make a new habitation, the caterpillar 

 fastens itself on the under side of a leaf of the Potamogeton. 

 With its mandibles it pierces some part of this leaf, and 

 afterwards gradually gnaws a curved line, marking the 

 form of the piece which it wishes to detach. "When the 

 caterpillar has cut off, as from a piece of cloth, a patch of 

 leaf of the size and shape suited to its purpose, it is pro- 

 vided with half of the materials requisite for making a tent. 

 It takes hold of this piece by its mandibles, and conveys 

 it to the situation on the under side of its own or another 

 leaf, whichever is found most approprite. It is there dis- 

 posed in such a manner that the under part of the patch 

 — the side which was the under part of the entire leaf — is 

 turned towards the under part of the new leaf, so that the 

 inner walls of the cell or tent are always made by the 

 under part of two portions of leaf. The leaves of the 

 potamogeton are a little concave on the under side ; and 

 thus the caterpillar produces a hollow cell, though the rims 

 are united. 



The caterpillar secures the leaf in its position by threads 

 of white silk. It then weaves in the cavity a cocoon, 

 which is somewhat thin, but of very close tissue. There 

 it shuts itself up, to appear again only in the form of the 

 perfect insect, and is soon transformed into a chrysalis. 

 In this cocoon of silk no point touches the water ; whilst 

 the tent of leaves, lined with silk, has been constructed 

 underneath the water. This fact proves that the cater- 

 pillar has a particular art by which it re23els the Avater 

 from between the leaves. 



When the 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 tent or habitation which it may carry everywhere about 

 with it. It begins by slightly fixing the piece against 



