164 



AMERICAN SPIDKKS AND THEIK SPINNINGWORK. 



in the form of flossy loops of curled thread, seemed to be laid down as 

 straight linos. As a consequence the surface after spinning did not show 



the floss}^ appearance, for examj)le, of a bit 

 _ of cotton wool, but rather the smooth and 



^^-ft~ \-^'lt^- compact appearance of a spool of closely 

 wound sowing thread. Not that the co- 

 coon thread was wrapped quite as closely 

 as the spool, but in a general way it pre- 

 Fios. 200, 201. Epeira strix enclosing her eggs seuted that appearance. This effect was 



within silk floss. (After Emerton.) , i i ii i j? ii i 



promoted by the use made oi the leg, 

 which was laid flat along the cocoon, and the last two joints pressed against 

 it, thus serving to compact the threads. 



When I returned at twelve o'clock and ton minutes, work upon the 

 cocoon had ceased, and the spider was putting in the finishing lines of 

 the maze of interlacing threads within which the cocoon of this species is 

 ordinarily suspended. I was somewhat surprised, however, to find that no 

 change had occurred in the exterior appearance and character of the mass 

 since I had left it. T had supposed that some kind of a varnish would be 

 laid upon the surface, having the idea that perhaps some modification or 

 degree of the material which composes the viscid beading of the snare 

 would be used to cover in the interspaces of the silk on the exterior, thus 

 making it partly weatherproof. But Prima's cocoon showed only the 

 glossy white silken surface with a little tinge of yellow, and no trace of 

 anything but the original silk as it had issued from the spinnerets. 



This was in sharp contrast with a cocoon in the trying box just above, 

 which had been made by another Argiojjo tw'o days before, but whose 

 making I was not able to see. I had watched it late into the night, and 

 in the morning when I came to look at it the cocoon was entirelj' finished 

 and the sjiider engaged in weaving 

 around it its protection of netted lines. 

 But the surface of the cocoon had been 

 treated in the ordinary way, and pre- 

 sented the customary yellowish brown 

 tint, had the hard, dry, parchment like 

 feeling, and gave out the crackling 

 sound which is almost invariable in 

 cocoons of this species. I have little 

 doubt that it is treated in some 2ie- 

 culiar way, immediately after comple- 

 tion, in order to produce this effect, but Fig. 202. Female Theridlum tepidariorum finishing 

 , .II' 1 , 1 cocoon. Other cocoons hanging in the nest. 



as yet trie method is unknown to me. 



The spider Prima probably began to make her cocooii shortly before 

 five o'clock of the morning, and must have continued weaving at least 

 until half past ten. She was therefore engaged five hours, at the least, 



'M-/ 



