PART II -MATERNAL INDUSTRY AND INSTINCTS. 



OHAPTEE IV. 

 MATERNAL INDUSTRY : COCOONS OF ORBWEAVERS. 



The maternal industry of spiders is concerned chiefly in tlie preparation 

 of the silken sac within which the eggs are deposited. It includes also the 

 various methods by which this sac, when woven, is disposed of in order 

 to secure a greater protection for its contents from exigencies of climate 

 and weather, and assaults of enemies. I shall treat this part of my subject 

 after the methods previouslj' adopted, and describe in detail the cocooning 

 habits of Orbweavers, and then present brief studies of the cocoonery of 

 typical species of other tribes, with a view to comparison as to various 

 points, such as the form, number, modes of preservation, and construction. 



I. 



Among Orbweavers, the largest cocoon known to me is that of Basket 

 Argiope. It is usually a pyriform or globular flask or sac of stiff, parch- 

 ment like, yellowish silk, suspended in various sites by a series 



_, of short lines passing from all i)arts thereof to surrounding ob- 



Cocoons. 1 » 1 to 



jects. These lines, at the points of attachment to the cocoon, 

 diverge into minute conical or pyramidal deltas, similar to tliose formed to 

 anchor the usual dragline when the spider walks. 



The objects upon which the cocoons are hung depend, of course, upon 



the local habitat of the individual. For the most part, Argiope spins her 



web in low positions ; on the tall grasses growing in the angles of a rail 



or "worm" fence; on the miscellaneous shrubbery that will be seen along 



the edge of a New England stone fence ; in the low bushes of various sorts 



found in fields, lanes, the skirts of woods, and out of the way places — one 



will be sure to meet these pear shaped objects in October or early November. 



A collection tliat lies before me as I write will be sufficiently typical 



of the positions in which Argiope spins her cocoons. Here is a cluster of 



tall grasses, upon which two cocoons are hung. One, with a brown 



. °°^^' external case, is suspended within a series of closely intersecting 



" yellowish threads, which are lashed to the stalks of the grass 



eight inches from the roots. Just within the little concavity formed by the 



stems as they have been puUed together in a circular position, the little 



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