Temporary Social Parasitism and Slavery in Ants. 179 
This we now know is not always the case. Morice 
recorded the capture of four f f and two winged ¢ 2? ina 
nest of Formica sanguinea at Weybridge on July 13th 
1900, and Barnes found four dedlated and one winged 
Jusca 2 ina nest of sanguinea at Wellington College on 
September 6th, 1902. 
To again test the fact that sanguinea 2 9 are unable to 
found colonies by themselves, I isolated a number of ? 2 
obtained at Woking in April. They were placed in bowls 
of damp sand, with pieces of damp sponge for them to 
shelter under. They hid under the sponges, but never 
attempted to dig a cell. A few eggs were scattered about 
on the surface of the sand, which never hatched. The 
2 2 paid no attention to these eggs, and eventually all 
the queens died. Viehmeyer has proposed yet another 
method of colony founding. He suggests that a 2 of 
sanguinea when ready to lay may seek a fusca 2 in the 
same condition, and both lay together. When the fusca 
brood reaches the pupal stage, the sanguinea 2 takes 
possession of them. This will account for new nests found 
in which the sanguinea 9 9 are as old, or older, than the 
Jusea 8 3. 
If Darwin had known, as we know to-day, that the 
queen sanguinea does not herself found her colony, but 
from the very first steals the fusca pupae, one of his 
greatest difficulties would have been removed, viz. the 
attempt to understand how it is that the workers which 
do not breed inherit the slave-making instinct. 
Formica exsecta, Nyl.—The queens of this species also 
found their colonies in nests of F. fusca. They are much 
smaller in comparison to their workers than are those of 
rufa or sanguinea, and are also of a darker colour. They 
can thus more easily get accepted by the fusca 9 G, as 
Wheeler showed to be the case with the small 2 2 of 
F. consocians with 3 9 of F. incerta in America. On May 
27th, in company with Mr. Banks of Corfe Castie, I found 
a small nest of F. exsecta at Bournemouth. It was of the 
usual exsecta type, but quite small. On being examined 
it proved to contain both exsecta and fusca. The § 9 of 
the latter, however, were present in considerably greater 
numbers than those of the former. Here undoubtedly 
was a new exsecta nest, founded by a young ¢ of that 
ant, which had entered a fusca nest and been accepted by 
them. None of the larger and older nests of exsecta 
Nez 
