304 
Psyche 
[December 
the guardianship of one of two “home” adult workers) into that 
colony and noting the reactions of the “hosts”. 
(b) By testing reactions between colonies drawn from the same 
or different populations long enough after they had been sepa¬ 
rated (three to four years in most cases) so that at most a very 
small proportion of the workers living at the time of collection 
survived to participate. Thus the participants entirely or for the 
most part, had never been individually subjected to such tests. 
Thus, while the individual might itself have been conditioned by 
the distinctive colony odor of its own community, that distinc¬ 
tion must persist over more than one worker generation. Results 
were as follows: 
1. Young Ants Returned to Parent Colony 
Young workers of R. metallica normally eclose from cocoons in a 
quite advanced stage of pigmentation and actively participate in 
colony functions within one or two days. This facilitated experimen¬ 
tal procedures considerably, though the question remained open, of 
course, as to whether the “receiving” adults in the main community 
might distinguish their younger sisters or progeny on an age basis. 
The colony used in this work (Y-l) had been collected from the 
Sutherland population on December 30, 1959, and maintained as a 
laboratory group thereafter. 
Test 111 
A group of cocoons from colony Y-l was isolated on September 
17, 1962, with 2 adult and 2 callow nurses. 
On March 10, 1963, 20 workers (at least 18 of which must have 
been “strangers” to the home community) were reintroduced to the 
main colony with clean forceps. All were entirely compatible as 
shown. 
Test til 
Test No. 
Reaction 
2 
3 
4 
5 
6 
Fully compatible (A) 
Fully compatible (A) 
Fully compatible (A) 
Fully compatible (A) 
Fully compatible (A) 
Fully compatible (A) 
