164 



AMERICAN SPIDERS AND THEIR SPINNINGWORK. 



fauna, while Gasteracantha has never been found farther nortli than tlie 

 southern areas of our Gulf States. Both these genera, like Nephila, aj)pear 

 to be more especially cliaracteristic of the tropical spider fauna, among 

 which they also have a great variety of prolific and peculiar species. 



One's curiosity is sorely puzzled to know why our three nortliern repre- 

 sentatives of xVcrosoma have been able to find and hold a lAnce among 

 the fauna, not only of tlie temperate, but of tlic more northern areas, 

 while otlier species, and the genus Gasteracantlia in all species, have ceased 

 their northward march at the line alreadj^ indicated. Or has the progress 

 been in the reverse direction — from the north towards the south? And 

 are our indigenous species of Acrosoma tlie survivors of a fauna that once 

 held sway throughout the region stretcliing from New England to the 

 Pacific? 



IV. 



Closely associated with spiders making a liorizontal snare is the Bas- 

 ilica spider, the sole known re])resentative of species tliat spin what I have 



called a Domed orb. Tiie 

 history of this species, 

 wliicli I have heretofore 

 recorded, is as follows :i 

 In the month of June, 



1S77, 1 was en- 

 Domed 

 Orbs, 

 Epeira 

 basilica. 



cd 



Flu. 154. The dome shaped snare ut the liasihca spider, r, the reti- 

 telanan snare ; d, the dome. 



campcii Upon 

 Ibc hills of the 

 Colorado River 

 of Texas, a few 

 miles southwest of Aus- 

 tin, studying the baliits 

 of the agricultural and 

 cutting ants.'^ A limited 

 portion of my time was 

 given to observing spi- 

 ilers, in tlie coui\se of 

 which the object of this 

 sketch was discovered. 

 Her snare was liung about 

 two feet from the ground, 

 tipon a bush whicii stood 

 in the midst of a grove 

 of young live oaks. This 



' Proccerlin^s! Academy of Natural Sriences of Philadolnhia, 1878, pat;i'S 124-lo2. 



^Observations upon the former species are recordeil in a volume entitled "The Agricul- 

 tural Ant of Texas," J. B. Lippineott Company, Philadeli)hia. For some account of the 

 Cutting Ants sec "Proceedinns Acad. Nat. Sci. Phila.," 187it, iiage :«. and Chapters XIII. and 

 XIV. in my popular work entitled "The Tenants of an Old Farm." 



