2-48 BlUiugrajjhical Notice. 



that any such thf?ory shall fit the known facts of biology as well as 

 those of geolog}' and physics. 



Some of the most interesting of Mr. Belt's zoological observations 

 relate to ants, of whose habits he was e'V'idently a close obseryer. 

 Thus with regard to the (Ecodomce, or leaf-cutting ants, he is the 

 first to record any thing of the internal economy of their vast sub- 

 terranean dwellings. He had to do battle with these fearful depre- 

 dators in his attempts to cultivate various useful and ornamental 

 plants in his garden, and gives an amusing description of his en- 

 deavours to extirpate them by pouring buckets-full of diluted car- 

 bolic acid down the broad passages which lead to their cavernous 

 abodes. But the most extraordinary thing he relates of them is 

 that their habitual food is a fungus, which thej' sedulously grow in 

 their underground chambers. In fact, it is for this purpose, he 

 found, that they require the vast quantity of pieces of leaves which 

 the workers spend nearly all their lives in cutting from young trees 

 and carrying to their abodes — the leaves not being used as food, nor 

 as a thatch for their nests, as had been surmised by other writers, 

 but being stored in chambers, where, in decaying, they produce a mi- 

 nute fungus, on which the larvae and small workers seem to feed. 

 He gives also many interesting details regarding the various species 

 of Eciton, or foraging ant, which hunt through the Tropical- American 

 forests in large armies, and states a fact which is entirely new, Adz. 

 that they construct no formicarium, but have only temi^orary abodes. 

 The facts cited in illustration of the reasoning-powers of ants are 

 numerous throughout the volume ; it is a subject on which he tried 

 many experiments with curious results. The best case he gives is 

 that of a marauding procession of (Ecodomce tunnelling under the 

 rails of a tramway to avoid being crushed by the passing waggons. 

 One day when the waggons were not running, Mr. Belt stopped up 

 their tunnel with stones ; but although great numbers were thus cut 

 oW from their nest, they would not cross the rails, but set to work 

 making fresh tunnels underneath them. It is impossible to do more 

 than allude to the vast store of suggestive facts and reasoning on this 

 subject contained in the volume. 



The relations of insects to flowers in regard to cross-fertilization 

 form the subject of many original observations, recorded and argued 

 out to definite conclusions with great keenness and circumspection. 

 The same may be said with reference to another less-worked phase 

 of insect- and plant-relationship, viz. the special adaptations of leaves 

 to attract pugnacious ants as defenders of the plants against defoh- 

 ation by leaf-cutting ants, caterpillars, and other phytophagous ani- 

 mals. This subject is dealt with in a series of observations on the 

 bull's-horn-thoru Acacia, on species of Mclastoma having glandular 

 swellings at the bases of their leaves containing a sweet fluid to 

 attract ants, and on the Cecropia trees, which invite protecting ants 

 to dwell in their hollow chambered stems. The ants thus attracted 

 form, as Mr. Belt expresses it, a most efiicicnt standing army for the 

 plant. 



Mimetic resemblances come in for a large share of Mr. Belt's 



