ALLEN, FORAY OF ANTS. 15 



"while others were still white, having just left the pupa case.* 

 My operations produced great agitation in the ranks of the 

 plundering species, information of the disturbance spreading 

 so rapidly, that, in a few seconds, scores had come together, 

 where there were but three or four before, exceedingly irri- 

 tated and eager to fasten on my forceps and hands. I col- 

 lected at different points along the train, with invariably the 

 same behaviour on the part of the ants, they immediately 

 gathering about me, coming from both directions. I noticed 

 that, within a few minutes after I first molested them, the 

 procession began to diminish in that portion towards the 

 plundered ant hill, and ten minutes after only a few of the 

 F. sangiiwea could be seen, and these were near their own 

 galleries, each returning with its captive. Whether they had 

 finished their labor for the morning, or suspended it on ac- 

 count of being molested, I could not fully ascertain, though 

 it was probably the former. An examination of the plun- 

 dered mound, made a few hours after, when perfect quiet had 

 returned, showed that it had not been fully exhausted of its 

 inhabitants ; a few of the old ants remained, as well as an. 

 abundance of their helpless young. A few of the F. san- 

 guinea were also there, apparently left as a garrison. On 

 disturbing the colony of F. sanguhiea both species came out, 

 but the captives were much less in number and did not 

 manifest the rage exhibited by the proprietors. Examining 

 the formicaries of both species two days later, the plun- 

 dered one was found entirely empty, all of both adults and 

 young having been removed, while the other was well 

 stocked with both species, the slaves, however, being much 

 less in number than the F. sanguhiea, and much less earnest 

 in resisting my attack. 



"^ The species, upon which the foray of Formica sanguinea 

 in this instance was made, was an ant entirely black in 

 color, rather larger in size than the F. sanguinea, but evi- 

 dently a weaker species^ having a smaller head, slenderer 

 antennae, legs and thorax, but a larger abdomen. It is 

 possibly a species common to both Europe and North Amer- 

 ica, though it may prove to be undescribed. The young, 



* A few of these specimens have been communicated to the Essex In- 

 stitute, and the remainder to the Museum of Comparative Zoology. 



