106 ANIMAL INTELLIGENCE. 



dry. MacCook, however, 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 of 

 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- 

 <;umference 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 



