Prof. 0. Heer on the House Ant of Madeira. 219 



placed in the vessel, were not divided, but carried off quite 

 entire. To ascertain the strength of these little creatures, I tied 

 with a thread first two, then three and four dead window-flies 

 together, and they dragged even this load of four flies first to the 

 perpendicular piece of wood to which the level thread was 

 fastened, aloft, then horizontally along this, and then down the 

 perpendicular thread till they brought it to the hole in the wall. 

 Here the flies were first pulled in pieces, because the hole was 

 too small to let them be carried through it entire. This carriage 

 of the flies over the thread stretched through the air, was ex- 

 tremely droll to see. A single fly would sometimes be dragged 

 away by only two ants ; on the load of four flies were mostly 

 from six to twelve labourers employed. Most of these had laid 

 hold with their fangs in front, and pulled, going backwards, at 

 the load ; the rest had fastened on the other side, and pushed, 

 going forwards, in a straight direction, holding on meantime by 

 their legs to the thread. The motion forwards was always by 

 short impulses ; on each jerk there followed a longer or shorter 

 rest. Men are well known to do the same in shoving along a 

 great load : when several share the work, it is always managed 

 by a cry (Yo ho), that all may lay hold at once, and so bring 

 equally to bear the force applied. A like co-operation in these 

 ants could not but be discerned : the hinder pushed at the same 

 time as the front ones pulled, and at the same time they left off 

 and rested for an instant together. But by what kind of means 

 this unanimity in their operations was attained, I was not able 

 to discover. The most remarkable thing moreover was, that 

 sometimes all let go together, and a single one held the whole 

 load in suspension. Here therefore again some agreement must 

 have taken place, for not one fly ever fell to the ground : there 

 was always an ant ready to hold on : but had all left loose at the 

 same time, the load must have naturally fallen down. The load 

 was altogether held by the fangs only ; with their legs the ants 

 clung fast to the thread, wherein the peculiar curvature of the 

 first joint of the foot, and the remarkable claw (see fig. i. 6 b,c) 

 corresponding thereto, had each essentially their share. Thus a 

 single, and that an unusually minute ant, was able, hanging to 

 a thread, to support four flies. What immense muscular power 

 in the fangs and legs does this display ! * 



Whilst the ants were transporting this burden, they were not 

 easily disturbed at their work ; whilst otherwise they quickly 

 run off when they are meddled with. For example, if one lifts 

 up a fruit full of ants, or shakes it, they hurry out as fast as 



* A house-ant (dried) weighs -^q of a milligramme ; but four window- 

 flies (also dried) 18^% of a milligramme. Thus this ant was able to bear 

 a load 376 times its own weight. 



