380 



AMERICAN SPIDERS AND THEIR SI'INNINGWORK. 



insectivorous liabits embrace the aranead nations also in their menu. j\[on- 

 keys eat tliem ; Hentz discovered a rat eating Oxyopes viridans;^ and we 

 have an account, wliich may pass for what it is worth, of even sheep 

 upon tlie Steppes of Russia devouring certain ground spiders.^ 



Many sjiiders while yet immature fall victims to the voracity of their 

 own si)ecies. I have elsewhere considered the charge of cannibalism as 

 lodged against sj)iderlings while yet within the cocoon, sliow- 

 , ,. . ing that as a rule their cradle life and earliest babyhood are 



largely exempt from the perils of internecine hunger. But when 

 once the .solitary habit of the race has compelled the individuals to seji- 

 arate and dwell apart. Nature relaxes- her restraining influence and hunger 

 converts all available oljjects into legitimate prey. After this period it is 

 not possible to defend our aranead friends against the charge of canni- 

 balism, even of the most revolting 

 kind. Brotliers and sisters eat each 

 other u}) without hesitation, and since, 

 naturally, fellow broodlings are likely 

 to pitch their tents and spin their 

 snares in closest contiguity, it comes 

 to i)ass that many of every brood are 

 devoted as sacrifices to the growth 

 and development of the few surviv- 

 ors to whom Nature has committed 

 the perpetuity of the species. Out- 

 side of these limits, everywhere, spi- 

 ders will prey upon their kind as 

 opportunity allows, even the hours 

 allotted to courtship and amatory em- 

 brace not being whollj^ exempt from 

 the perils of this general tendency. 



II. 



Perhaps the most persistent and 

 destructive natural enemies of spiders 

 are certain hyraenopterous insects be- 

 longing to the large family of wasps 

 known popularly as mud daubers and diggers. 



It has often been remarked by ordinary observers that wasps can visit 

 a spider's web not only with impunity, liut as a successful assailant of 

 the occupant thereof. This fact has crept into literature, and is embalmed 

 by Goethe in a striking allusion to his father. "Willingly," he writes in 

 his autobiography, " as I have made myself familiar with all sorts of 



^ Spiders of the U. S., page 46. ^ Walckenaer, Apt., Vol. I., page 172. 



Fig. 322. A wasp plucking an Orbweaver from 

 its snare. 



