Ridley.—Symbiosis of Ants and Plants. 483 
bud has ceased to be necessary, their reflection and continued growth, the 
production of food-bodies, are all modifications which can have no other 
function than that of attracting the ants and retaining their services as 
guards. It has been shown too that their guardianship is of the greatest 
importance to the plant, which almost invariably suffers seriously from the 
attacks of caterpillars when they are absent. 
Very similar to the case of Macaranga are those of Cecropia adenopns , 
as described in Schimper’s Pflanzengeographie, and of Acacia cornigera. 
These seem to be truly myrmecophilous and the symbiosis of the ants with 
the plants appears to be as complete as possible. 
EXPLANATION OF PLATES XXXV AND XXXVI. 
Illustrating Mr. Ridley’s Paper on Symbiosis of Ants and Plants. 
PLATE XXXV. 
Macaranga triloba, Muell. Arg. 
A. Bud showing bud-bracts spreading. 
B. Portion of stem with bud-bracts reflexed and forming a ring. 
C. Bud-bract from inside, showing food-bodies. 
D. Bud enclosed in its bracts, with bladder-glands. 
E. Section of bud-bract and stem, showing food-bodies. 
F. Bladder-glands. 
G. Food-body. 
H. Section of bud-bract with a food-body. 
/. Under portion of young leaf with bladder-glands. 
PLATE XXXVI. 
Macaranga hypoleuca } Muell. Arg. 
A. Young stem, showing dilatation of internodes unoccupied. 
B. The same in section, with pith-bars. 
C. Bud with spreading bud-bracts. 
D. Section of stem occupied, with two coccids and the perforation made by the ants. 
E. Young leaf with nectaries and food-bodies. 
F. Portion of young leaf much enlarged with nectaries, and food-bodies. 
G. Nectaries at different stages of growth. 
