292 HENRY C. MCCOOK. 



(^Formica) Pennsylv aniens, but the losses inflicted during the occa- 

 sional conflicts with these creatures must be quite small. Spiders of 

 the various sub-orders destroy some. At the foot of one hill between 

 two stalks of grass a female of Argiope fasciata, one of the most 

 beautiful of our indiginous orb-weavers, had spread her snare. An 

 ant which was fed to her was seized, rapidly swathed in the usual fine 

 white web, and fed upon. The numerous sedentary spiders that spread 

 their webs upon trees and bushes must ensnare a goodly number. 

 A variety of Formica rufa which for several years has inhabited the 

 great clifi" at Rockland in Fairmount Park, finds a most formidable foe 

 in that ferocious line-weaver Tkeridium tepidariorum {yulgare, Hentz), 

 who spreads her great, strong snare in the recesses of the rock. I have 

 seen scores of ants clinging to these webs and have gathered up half- 

 handfulls of the dry carcasses underneath. The various genera of the 

 wandering spiders are no doubt formidable to single ants. On the 

 trees the abuscading Laterigrades and those swift-vaulting garroters, 

 the Saltigrades, must cut ofi" many a straggling forager. On the 

 ground, perils threaten the Formicidae from the powerful and ferocious 

 wolf-spiders {Lycosidse), and the familiar spotted tube-weaver {Agalena 

 nsevia), whose broad-sheeted, funneled snare is so widely spread among 

 the weeds and grasses. But we may well exclaim, what are these 

 among so many ? 



The birds may pick up a few. A gentleman who visited our camp 

 one day informed me that as he rode along he observed a large flock 

 of blackbirds in the woods, on the ground among the hills, a dozen 

 or more being on a hill apparently pecking at the ants. These birds 

 harbored in the woods several days, and although our party all watched 

 them closely nothing of the kind was again observed. Mr. Prough, 

 the farmer whose land and residence adjoin the wood, declares that 

 although crows freely cat the black Pennsylvania Carpenter Ant, no 

 sort of birds or fowl will touch these " pismires," as the fallow ants 

 are popularly called upon the mountain. Perhaps after all the chief 

 causes operating to limit the spread of this species are geological. 

 But until we know more certainly the geological conditions favorable 

 and adverse to their increase, the question must remain open. 



The species is found in abundance in the sandy barrens of New 

 Jersey. I have in my possession an artificial formicary of living 

 specimens sent me by Mrs. Mary Treat of Vineland. who during the 

 past summer has made many interesting observations upon ants, par- 

 ticularly the kidnapping Formica sanguinea. The New Jersey rufas 



