274 ENTOMOLOGY 
The ant-trees (Cecropia adenopus) of Brazil and Central 
America have often been referred to by travelers. When 
one of these trees is handled roughly, hosts of ants rush out 
from small openings in the 
PIG. 267. 
stems and pugnaciously at- 
tack the disturber. Just 
above the insertion of each 
leaf is a small pit (Fig. 265, 
a, b) where the wall is so 
thin as to form a mere dia- 
phragm, through which an 
ant (probably a_ fertilized 
female) bores and reaches a 
hollow internode. To es- 
tablish communication  be- 
tween the internodal cham- 
bers, the ants bore through 
the intervening septa (Fig. 
266). They seldom leave 
the Cecropia plant, unless 
disturbed, and even keep 
Cecropia adenopus. Base of petiole showing herds of aphids in their 
“Miiller’s bodies.’’ Slightly reduced. - : 
abode. The base of each 
petiole bears (Fig. 267) tender little egg-like bodies (“ Mul- 
ler’s bodies”’) which the ants detach, store away and eat; 
the presence of these bodies is a sure sign that the tree 1s un- 
inhabited by these ants, which, by the way, belong to the genus 
Agteca. 
It is too much to assert that the ants protect the Cecropia 
plant in return for the food and shelter which they obtain. 
All ants are hostile to all other species of ants, with few excep- 
tions, and even to other colonies of their own species; so that 
their assaults upon leaf-cutting ants are by no means special 
and adaptive in their nature, and any protection that a plant 
derives thereby is merely incidental. Furthermore, hollow 
stems, glandular petioles and pitted stems are of common oc- 
