AMERICAN HYMENOPTERA. 283 



element of considerable peril. There is no supposition more likely 

 than this; at least there is not the slifjhtest improbability in such. 

 A glance at this thoroughly honey-combed block shows at once, with- 

 out any special knowledge of the resisting force of woods, that the 

 strength of the beam twelve by ten inches, from which it was cut 

 must have been greatly weakened by the excavation. It is possible 

 that the depredations of insects, as the carpenter ants and white ants 

 upon the wood-work of bridges and other public works, may not have 

 received due attention from our public carriers. 



However, that no exaggerated conclusion or needless alarm may 

 arise from this statement, I am able to modify it somewhat by giving 

 approximately the period of time consumed in bringing this formicary 

 to its present condition. The miller had observed the colony at work 

 upon the beam for more than five years. By inquiry of one of the 

 proprietors, the existence of the colony was traced back certainly 

 three, probably five years beyond that date. Thus eight or ten years 

 have been spent in scraping out this labyrinth of galleries and vaults. 

 No doubt other' colonies under more favorable conditions may work 

 more rapidly. Nevertheless, the fact of such moderate progress, 

 greatly modifies the conditions of danger. However, even the slightest 

 sign of threatened peril in such a case is worthy of the profoundest 

 caution and consideration. The trees within which by observation or 

 credible report this species of ant has been found working, are maple 

 cedar, red oak, black oak, hickory, and pine. 



It is not, perhaps, a matter of great economical importance to deter- 

 mine the agents which, as natural enemies, counter-work to prevent 

 the destructive increase of the Pennsylvania ants. It is, however an 

 important item in the natural history of the creature. I am not able 

 to contribute much to this point of inquiry from observation. I have 

 learned from a farmer on Brush Mountain, that the crows feed upon 

 them freely. Doubtless many other species of birds find them a 

 tempting and delicate morsel. The hunters in the mountains declare 

 that the bears eat these ants, tearing old logs in pieces in order to 

 break up the formicaries and reach their inhabitants.* I have further 



»This fondness of the bear for ants has the authority of very ancient tradi- 

 tion. Thus (says Cowan), the "Treasurie of Avncient and Moderne Times," 

 printed A. D., 1613, avers that " the Bear, being poysoned by the Hearbe named 

 Mandragoras or Mandrake, doth purge his bodie by the eating of Ants or 

 Pismires." Long before this Plutarch wrote (the quotation is from Holland's 

 translation), that "the bear finding herself, upon fullness, given to loth and 

 distaste for food, she goes to find out Ants' nests, where she sits her down, 

 lolling out her tongue, which is glib and soft with a kind of sweet and slimy 

 humour, until it be full of ants and their egges; then draweth it she in again, 



