106 
ANIMAL INTELLIGENCE. 
dry. MacCook, nowever, neglected to make any experi- 
ments on this subject. Neither has he been able to throw 
any light upon the question as to why the stored seeds do 
not germinate, and is doubtful whether the habit ol 
gnawing the radicle of sprouting seeds, which prevails 
in the European species, is likewise practised by the 
American. On two other points of importance MacCook’s 
observations are also incomplete. One of these has refer- 
ence to an alleged statement, which he is disposed to 
believe, that when some ants in a community have been 
killed by poison, the survivors avoid the poison : he, how- 
ever, made no experiments to test this statement. 
The other main point on which his observations are 
defective has reference to a remarkable statement made 
by Lincecum in the most emphatic terms. This state- 
ment is that upon the surface of their disk the ants 
sow the seeds of a certain plant, called ant-rice, for the 
purpose of subsequently reaping a harvest of the grain. 
There is no doubt that the ant-disks do very often sup- 
port this peculiar kind of grass, and that the ants are 
particularly fond of its seed; but whether the plant is 
actually sown in these situations by the insects, or grows 
there on account of these situations being more open 
than the general surface of the ground — this question 
MacCook has failed to answer, or even to further. We are, 
therefore, still left with Dr. Lincecum’s emphatic assur- 
ance that he has witnessed the fact. His account is that 
the seed of the ant-rice, which is a biennial plant, is sown 
in time for the autumnal rains to bring up. At the be- 
ginning of November a green row or ring of ant-rice, 
about four inches wide, is seen springing up round the cir- 
cumference of the disk. In the vicinity of this circular 
ring the ants do not permit a single spire of any other 
grass or weed to remain a day, but leave the aristida, or 
ant-rice, untouched until it ripens, which occurs in June of 
the next year. After the maturing and harvesting of the 
seed, the dry stubble is cut away and removed from the 
pavement or disk, which is thus left unencumbered until 
the ensuing autumn, when the same species of grass again 
appears as before, and so on. Lincecum says he has seen 
