I04 Bulletin American Museum of Natural History. [Vol XXII, 



deeper insight into the activities of female ants before we can hope 

 to solve many of the problems suggested by the instincts of the 

 "workers. 



POSTSCRIPT. 



While the foregoing pages have been going through the press, a 

 few facts of considerable interest in connection with both temporary 

 and permanent parasitism among ants have come to light. 



Mr. A. P. Morse has sent me a number of ants which were ap- 

 parently living as a mixed colony under the bark of a pine tree at 

 Sherborn, Massachusetts. The specimens comprise workers of For- 

 mica fusca var. suhcenescens and workers and a female of F. impexa, 

 which I originally described from the Porcupine Mountains of northern 

 Michigan. The female is very small and closely resembles the females 

 of F. m^icrogyna, nevadensis , and nepticula. Probably, therefore, F. 

 impexa is a temporary parasite like F. consocians . 



Forel has just published the interesting observations of Dr. 

 Santschi of Kairouan, Tunis, on the workerless ant Wheeleria sant- 

 schii, which is a permanent parasite in the nests of Monomorium, 

 salomonis. (Moeurs des Fourmis Parasites des Genres Wheeleria et 

 Bothriomyrmex. Rev. Suisse Zool., XIV, pp. 51-69, 6 figs.) The 

 young fertilized Wheeleria females were seen to enter the Monomorium 

 nests, and were at first pulled about by the workers. In the course 

 of a few hours, however, these females were definitively adopted. 

 Santschi has made the very significant observation that the Mono- 

 moriurn workers kill their own queen and transfer their allegiance to 

 the parasites. It now seems probable that the absence of the incerta 

 queens in colonies that have adopted consocians queens may be due 

 to similar matricidal instincts on the part of the workers. 



Forel in his ' Fourmis de la Suisse ' described a mixed colony of 

 the Dolichoderine Bothriomyrmex meridionalis and Tapinoma errat- 

 icum without being able to explain its origin. Santschi has just 

 made several observations which indicate that the Bothriomyrni'^x 

 females seek adoption in the Tapinoma nests, but as pure colonies 

 of each of these species are common, it is probable that the para- 

 sitism is of the temporary type seen in F. consocians. 



EXPLANATION OF THE PLATES. 



PLATE VIII. 

 Fio. I. — Queen of carpenter ant {Camponotus pennsylvanicus) with incipient 

 colony consisting of three minim workers and a packet of young 



