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ascends to about sixty feet in many loops and tangles. The 

 leaves remind one greatly of those of Celastriis scandens. At 

 other places in the garden are similar immense tangles of Gnetums, 

 which produce a very dense shade. The systematic collection of 

 Gnetums, located on the island, is composed of smaller plants, but 

 includes several different species. Many of them exhibit the 

 racemes of ellipsoidal fruits in various stages of maturity. 



At the south end of Canary Avenue, near the main entrance, 

 are several legumes of ecological interest. Plants of Humholdtia 

 laurifolia reach a height of about 25 feet, with crooked irregular 

 spreading branches, which at first sight appear diseased. Num- 

 erous ants are seen running on the trunk and collected on the 

 branches. They are particularly numerous under the coriaceous 

 appressed stipules, on the younger internodes where there are 

 scale insects, and in and around the racemes, where they appear 

 to be feeding, but upon what could not be ascertained. Their 

 nests are inside the internodes, which are hollow and in the 

 younger twigs somewhat clavate in shape. Here they cut a 

 hole about two mm. in diameter just opposite the leaf. When 

 the internodes become old, hard, and woody, the nests are 

 deserted. The orifice then becomes surrounded with callus, 

 and the whole wound becomes half an inch or more across, pro- 

 ducing the general diseased appearance of the tree. It is ob- 

 viously out of the question to try to draw any new conclusions 

 here concerning the relation of plant and ant, but it may be 

 remarked that when a pencil point or small stick was presented 

 to these ants, they ran away or dropped off the twig completely. 



Another legume, Brownea grandiceps, has a similar general 

 appearance. Here the large spherical flower buds are covered 

 with ants, although there is nothing apparent for them to feed 

 upon. These ants are fierce, and vigorously attacked the point 

 of a pencil when presented to them. 



Various other myrmecophilous plants are frequently seen in 

 the garden. Acacia sphaerocephala, with its hollow thorns and 

 food-bodies terminating the leaflets, grows just as described 

 years ago by Belt. Several species of the moraceous shrub 

 Conocephalns have lanceolate appressed stipules, up to two 



