324 SPECIMENS OF WEAVING. 



of an egg. This cocoon of the Hawthorn Saw-fly,* exposed 

 with its occupant all through the winter upon leafless hedges, 

 is composed of a material tough as leather, but much harder 

 (also an animal secretion). Here is an empty one with a 

 curious lid set open as for the exit of the perfect fly, which, 

 furnished with an adapted tool for the cutting of this sin- 

 gular trap-door, never fails in its circular excision to leave 



i 

 entire just such a portion as serves for an attachment and a 



hinge. 



In our survey here of the mechanisms and the manufactures 

 of insect weavers, we can hardly overlook entirely the instru- 

 ment by whose mechanic aid the hairy -legged Arachnes of 

 house and garden ply their art of ensnarement. Their lines, 

 though as fine, are (as their purposes require) infinitely stronger 

 than those of a caterpillar ; and why? but because instead of 

 being, as in the latter, composed of two, each single thread is 

 made of united thousands of (to the eye) invisible and almost 

 inconceivable fineness. 



This compound thread requires for its production a com- 

 pound instrument ; thus the spinneret of the spider is much 

 less simple than that of the caterpillar. We might suppose it 

 by careful scrutiny of the unaided eye to consist of five several 

 tubes, of which the prominent ends or orifices appear arranged 

 in star-like form, surrounded by a circle. But only let us 

 look at the same object as displayed here by a powerful mi- 



* Tenfhredo. 



