NATURAL SCIENCES OF PHILADELPHIA. 329 



cottiers, though many of them were slain during the war, they nevertheless 

 succeeded in destroying the entire colony, without any apparent disturbance 

 or unusual excitement about the great city. Their national works and govern- 

 mental affairs went on in their ordinary course, while the work of death was 

 being accomplished by their resolute bands of triumphant warriors. 



They do not interrupt, in any way that I have discovered, the small black 

 erratic ant, when it comes on their pavement. They even permit the erratic 

 ants to erect cities on any portion of the incorporated limits, and do not mo- 

 lest them. It may be that the little fellows serve them some purpose. But 

 when they build too many of their confederate cities on the pavement of the 

 agricultural ant, it seems to be an inconvenience to them some way, but they 

 do not go to war with them, nor attempt to rid themselves of the inconveni- 

 ence by any forcible means. They, however, do get clear of them, and that by 

 instituting a regular system of deceptive and vexatious obstructions. The 

 deception is manifested in the fact that it appears to have suddenly become 

 necessary to raise the mound two or three inches higher, and also to widen the 

 base considerably. Forthwith are seen swarming out upon the pavement hosts 

 of ants, who go rapidly to work, and bringing the little black balls 

 which are thrown up by the earthworms in great quantities everywhere in the 

 prairie soil, they heap them up, first at the base of the mound, widening till all 

 the near erratic ant cities are covered up. At the same time, they raise the 

 entire pavement an inch or so, and in prosecuting this part of the national 

 work deposit abundantly more balls upon and around the erratic ant cities 

 than anywhere else. The little ants bore upwards through the hard sun-dried 

 balls, which are constantly accumulating getting worse every hour until 

 the obstruction has become so great that they can no longer keep their cities 

 open ; and, finding that there is no remedy for the growing difficulty, they 

 peaceably evacuate the premises. There is found on almost every pavement, 

 at this season of the year, three or four small pyramidal mounds, that have 

 been constructed for the purpose of crowding out the little erratic ants. 



The extensive, clean, smooth roads that are constructed by the agricultural 

 ants are worthy of being noticed. At this season of the year their roads are 

 plainest and in the best order, because it is harvest time, and their whole force 

 is out collecting grain for winter supplies. 



I am just this moment in from a survey of one of these roads, that I might 

 be able to make an exact and correct statement of it. It is over a hundred 

 yards in length, goes through twenty yards of thick weeds, underruns heavy 

 beds of crop grass 60 yards, and then through the weeds growing in the locks 

 of a heavy rail fence 20 yards more ; and throughout the whole extent it is very 

 smooth and even, varying from a straight line enough, perhaps, to lose 10 or 

 12 yards of the distance in travelling to the outer terminus. It is from 2 to 1\ 

 inches wide ; in some places, on account of insurmountable obstructions, it 

 separates into two or three trails of an inch in width, coming together again 

 after passing the obstruction. This is the main trunk, and it does not branch 

 until it crosses the before-named fence, beyond which is a heavy bed of grain 

 bearing weeds and grass. Their prospecting corps travel far out, and when 

 they discover rich districts of their proper food they report it, and a corps of 

 foragers are immediately dispatched to collect and bring it in. 



11th June, 1863. My son, Dr. Leonidas, called my attention to an assem- 

 blage of the males and females of the agricultural ants (Myrmica molefaciens) 

 which took place about 2 P. M., and continued in session until 4 P. M. They 

 were all winged ants, and there were many thousands, perhaps millions, of 

 them, -thickly covering the ground over an area of 10? yards in length and 10 

 wide. They came from all directions, and were evidently the production of 

 many kingdoms of this wonderful species of ant. There must have been, at 

 least, five males to one female, and all parties were rushing hither and thither 

 over the entire area, described above, in a frantic, amative furor. Each female 

 would be found covered and wallowing on the ground with clusters of from 



1866.] 



