8 THOS. H. MONTGOMERY, JR. 



them. Probably the main value of the cocoon is to protect the 

 eggs from enemies, for were the eggs not enclosed they would 

 fall singly or in a mass to the ground, become removed from 

 the guardianship of the mother, and be subjected to a great 

 variety of rapacious foes. 



9. Relation of tJie Cocoon to the other Forms of Aranead Arclii- 

 tecturc. --On this important question i will dwell only briefly at 

 this point, reserving a fuller discussion for later. McCook ! con- 

 cludes : "The spinning work of spiders may be classified gener- 

 ally as, first, the Snare, spun for the capture of prey ; second, the 

 Enswathment, by which insects are disarmed and prepared for 

 food ; third, the Gossamer, used for purposes of aqueous and aerial 

 locomotion ; fourth, the Cocoon, spun for the propagation and 

 protection of the species; and fifth, the Nest, which is a domicile 

 more or less elaborate and permanent within and under which 

 the aranead dwells for protection against the exigencies of 

 weather and the assaults of enemies." Menge 2 had previously 

 called attention to the web that the males of certain species spin 

 for the deposition of their sperm, preparatory to charging their 

 palpi with it ; this has also been described by me (/. <r.), and it 

 may be called the "sperm-web." Then Wagner' in a most 

 important analysis of the architecture of spiders directed espe- 

 cially towards its phylogenetic significance, has distinguished the 

 web spun by some forms for protection during the moult ; and 

 then divides what McCook calls the " Nest" into : " La retraite- 

 construction, destinee pour la danciirc dc r araigncc, ou elle passe 

 tout son temps et qu'elle ne quitte que pour la chasse. A 1'epoque 

 de la ponte cette retraite pent servir de loge au cocon." And 

 into " Le 7/zV/- construction, destinee au sejour de la femelle et a 

 contenir le cocon." As far as I comprehend this distinction of 

 Wagner's, the "retraite" is a nest made by both sexes, the " nid" 

 one built by the female only. It seems to me questionable whether 

 this distinction of Wagner's is a valid one, and McCook's term 

 "nest" had best be retained without especial subdivision, though 

 surely different kinds of nests may be distinguished. 



'"American Spiders and their Spinning Work," Vol. I, Philadelphia, 1889. 

 2 " Ueber die Lebensweise der Arachniden," A'ensste Sc/ir. nntitrf. Ges. Danzig, 

 4, 1843. 



3 "L'Industrie des Araneina," Mem. Acad. Sd. Si. Pelcnboni^ (VII.), T. 42. 



