86 
F. E. Weiss. 
to remove indiscriminately any seeds placed in their pathway, a 
control experiment, such as were made by Sernander, was undertaken. 
The hard brown fruits of the burdock (Arctium Lappa) and fruitlets 
of the Wood Sage (Teucrium Scorodonia), both growing in the 
vicinity, were chosen. The former were larger and the latter smaller 
than the gorse seeds, but both have a rough surface and would be 
easier to carry than the smooth and slippery seeds of the gorse. 
The ants, however, did not touch the fruits of the sage and removed 
only one of the burdock fruits. This showed that they were 
capable of removing them, though they seemed to take very little 
notice of them. Their shape and size would, however, make them 
quite as convenient for the building of the nest as the other particles 
of wood and dead winter buds of the oak, which figured so largely 
as building material. 
A table showing the relative activity of the ants may be made 
as follows:— 
Number of seeds of 
Time 
3-15 
3-20 
3-25 
3-30 
Ulex 
5 
2 
0 
0 
Arctium 
5 
4 
4 
4 
Teucrium 
5 
5 
5 
5 
The table alone, however, does not represent the whole difference 
in the behaviour of the ants towards these three units of dispersal, 
“ Verbreitungseinheiten,” as Sernander calls them. The majority of 
the ants, intent possibly upon some definite purpose, passed by or 
even over the seeds of all three plants, apparently without taking 
note of them. Those which noticed the fruits of the burdock, made 
a hasty examination of them and then passed on. But when an 
ant stopped to examine the gorse seeds, it quickly found the bright 
orange caruncle and immediately began to bite and gnaw it. After 
that, it would rarely let the seed go, unless forced to do so by 
another ant and often two or three would struggle at it together. 
They generally set the smooth seed up on edge, holding it with 
their hindlegs, and, bending right over it, would apparently endeavour 
to remove the food-body or elaiosome. Unable to accomplish this, 
they would after a more or less lengthy struggle carry away the 
seed, not without some difficulty in getting a proper hold of it, 
eventually in all cases holding it by the soft and fleshy caruncle. 
Even when the caruncle was removed, the seeds were rapidly 
taken up by the ants, but I think, as Sernander found in the case 
of some of his experiments, that enough of the oily food-matter 
