146 Mr. ^ St. J. K. Donisthorpe on 
Clavigers into a small plaster nest for observation. From June 1st 
till the end of August I kept introducing $ 9 from the main nest 
into the small plaster nest, and they were always recognised and 
well received. On August 9th I introduced ^ 5 oi Solenopsis fugax 
taken with Lasins niger at Sandown. These were all killed by the 
Jiavus 9 9 • 
Here we see that ants from the same nest, separated 
for some time, were recognised and well received when 
brought together again. The experiment with Solenopsis 
was perhaps too severe a test, as the little parasitic ants 
had nowhere to hide in the plaster nest. 
I now come to my experiments with nests of Formica 
fusca and miJibarUs v. fusco-rnjiharhis and $ $ of Foomiica 
sanguinea. The modern view of the foundation of colonies 
by the Formica rufa, sanguinea and exsecta group supposes 
that the $ after her marriage flight enters a small nest of 
F. fusca, or one of its races, and takes possession of the 
pupae, being accepted by the woi’kers, or killing them if 
they prove to be antagonistic. This opinion is held, I 
believe, by both Father Wasmann and Prof. Wheeler. It is 
certainly the case that no one has ever witnessed, either 
in Europe or Ameiica, a $ of the rufa group founding a 
colony by herself, as may be seen in Zccsius and Myrmica, 
etc. I have observed quite small nests of F. rufa at 
Weybridge, which appear to have been quite recently 
formed, but I believe these to have split off from older 
nests, of which there are large numbers in the locality. 
I have also seen individuals of this species at Buddon 
Wood moving the whole nest to a new situation ; the 
pupae and entire contents of the nest and most of the nest 
materials being carried bodily away. For fifteen years I 
have known a very large nest at Weybridge. A few years 
ago a part of the ants in this nest moved to a spot close 
at hand. This year the ants in the old portion have 
moved to another spot near to the first new settlement, 
the old nest being deserted. Nests may spread in this way, 
but this has nothing to do with the founding of a colony 
by a single queen. I have no doubt some of the young 
queens return to the old nest after their marriage flight, 
but the problem is to ascertain the fate of those that do 
not. In order to test this question in the most exhaustive 
manner, we require a young female just after her marriage 
flight, and also a small, or impoverished, fusca nest. The 
