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as food for the protecting ants. Schimper found by experiment- 

 ing that the bodies were constantly reproduced, so furnishing 

 daily food. On cutting through the cushion of hairs the httle 

 ^gg-like bodies were found in all stages of development. Also, 

 by removing the outer leaves of buds on those trees where the 

 ants were Hving, the bodies were found in abundance and were 

 seized upon and eaten with great avidity by the ants. 



These egg-shaped bodies were found to consist largely of 

 albuminous matter and essential oil, substances which are not 

 otherwise given off by plants, except in case of seeds. So rich 

 an offering of plant-production without some corresponding use 

 is hardly credible, therefore Schimper concludes that these are 

 built up by the plant specially to maintain the colonies of ants 

 without whose protection it would be unable to reach any degree 

 of perfection. 



Another tree possessing similar features is a species o( Acacia, 

 Here the ants make their homes in the large hollow thorns. Food 

 IS also provided for them, in the shape of similar bodies of an al- 

 buminous nature, which occur in peculiar organs on the tips of 

 the leaves. Still other plants are described as possessing similar 

 remarkable examples of adaptation. 



In the third chapter of this article, the author treats of the so- 

 called extra-nuptial glands, that is, those not situated in the imme- 

 diate vicinity of the reproductive organs, whose use, therefore, 

 cannot be to attract insects as aids to fertilization. The so-called 

 -Belt-Delpino hypothesis regarding their use was confirmed by his 

 experiments. That is, that these organs serve as a means of at- 

 traction to those insects, which, in their turn, protect the plant from 

 msects which are more injurious, in fact fatal to its growth and full 

 development. He found that nearly all the plants supplied with 

 these glands were visited by ants, and, in several cases, was able 

 to prove directly that they afforded protection against the leaf- 

 cutting species. It is difficult to find any other use the plant can 

 make of the honey so secreted ; that it is not a waste product^ 

 whose retention might injure the plant, was shown by separating 

 the glands from the plant, and it was found to thrive equally well 

 as those whose glands were left intact. A considerable amount 

 of honey was found secreted by these glands, as by carefully re- 



