Antennophorus Uhlmaimi to Lasius mixtus. 621 



appendages are much more agita/fced when an ant passes 

 close by. If it pass near enough, the Acarid glues itself on 

 to its body by means of the cap of sticky material on the end 

 of one of its ambulatory feet, which it holds up ready for this 

 operation; and it can in this way sooii climb up and fix 

 itself in a good position on its host. Thi^ latter is surprised 

 and seeks to rid itself of the new comer, but, failing in this, 

 it becomes resigned very quickly as soon as the Acarid has 

 taken up one of its normal positions. 



Generally a working ant only carries a single Antenno- 

 phorus, but they may very often be seen carrying several. 

 In all cases, the parasites take up positions symmetrical with 

 the sagittal plane of their host's body, and it thus comes 

 about that the centre of gravity of the extra load is placed in 

 the sagittal plane of the carrying ant. 



The Acarids are also under the best conditions for not 

 hampering tlie movements of the ants, and, as a consequence, 

 for being the more readily tolerated by them. The Antenno- 

 phorus directs its antenniform feet towards the front of the 

 ant if fixed upon its head, and in the reverse direction if fixed 

 upon tlie abdomen. When an ant carries but one Antenno- 

 phorus, it is almost always placed on the head of the host. 

 The case (represented in the figure) of an ant carrying an 



Lasiiis mixtus bearing three Antennophorus Uhlmanni in their 

 normal positions. X 12. 



Antennophorus under its head and one on either side of the 

 abdomen is very common. The presence of one or more of 

 the parasites on the body of a Lasius does not prevent the 

 latter from taking its share in the work of the colony and in 

 particular the carriage of the larvae and rubbish. 



The Antennophorus attaches itself fi'eely to the naked 

 nymphs, but never to a nymph enveloped in a cocoon. Thus 

 in an experimental nest consisting of some fifty ants, all 

 carrying a single Antennophorus and accompanied by a certain 

 number of nymphs, I found on the following day a newly 

 emerged ant which bore seven Antennophori arranged 



