GENERAL COCOONING HABITS OF SI'IDEKS. 



149 



Cocoon of Pucetia aurora, opened 

 to show structure. 



by her cocoon. The outer covering of the eggs is quite thick, very white, 

 and apparently a little viscid; at least, it is quite adhesive. The exterior 

 tent has something of the same qual- 

 ity. (Fig. 182.) I sometimes find the 

 cocoon of Saltigrades enclosed within 

 the nesting cell and spun up within a 

 rolled leaf, as shown at Fig. 183, a beau- 

 tiful example of aranead sewing. Fig. 

 184 shows the leaf opened up, disclos- 

 ing the tubular nest, and again the 

 mass of eggs much enlarged and dis- 

 played against the egg case thrown back, 

 the egg case, of course, being within 

 the cell. 



One of the most elaborate cocoon nests woven by a Saltigrade spider 

 is that made by Phidi])pus opifex of California.' The examples both of 

 nests and s{)iders in my possession were sent me by Mr. W. G. Wright, of 

 San Bernardino, California. The cocoon nest is externally an egg shaped 

 mass of white spiimingwork, sometimes three inches long by two and a 

 half inches wide, but often less, as in Fig. 185, which is drawn natural 

 size. The outer part consists of a mass of fine silken lines crossing in all 

 directions and lashed to twigs of sage bush, within which it is enclosed. 

 This maze surrounds a sack or cell of thickly woven sheeted silk, irregu- 

 larly oval in shape, two inches long by one inch in width, and also at- 

 tached to the surrounding twigs. At the bottom this cell or tent is pierced 

 by a circular opening which serves the spider as the door of her domicile. 

 Like others of her genus Opifex lives and liibernates within this silken 



tent. Against an inner side of the 

 tent she spins a lenticular cocoon 

 (of double convex shape), consisting 

 of thick white silk, within which the 

 eggs are placed. When the cocoons 

 sent me reached Pliiladelphia many 

 young spiders had escaped and occu- 

 j)icd the package box. They were 

 about one-eighth' inch long, resem- 

 bling the mother, but less heavily 

 coated with gray. The spider her- 

 self is a large example, five-eighths 

 of an inch in body length, stout, the legs of moderate thickness, the whole 

 animal covered closely with grayish white hairs, the skin b'eneath which is 



Fia. 182. Cocoon tent and cocoon of Phidippus 

 morsitans spun upon a rock. 



> Tlie spider and its Imbits were originally noticed by me in Proceedings Acad. Nat. 

 Sci., Philadelpliia, 1883, page 270, 



