VII Relations Between Plants and Animals 135 



insects and mites. Sometimes they are like little wig- 

 wams formed from converging hairs, sometimes minute 

 caves or pits. They are not formed by the tenants, at 

 least not now, for they are natural to the plants, but they 

 are none the less well adapted to the use they serve, A 

 simple instance may be seen on the leaves of the lime-tree, 

 on the under surface of which, at points where two veins 

 of the leaf cross, there are little nooks tenanted by mites. 

 These do not injure the plant, but rather help it, for they 

 clear away minute fungi, and it is also possible that their 

 nitrogenous waste-products are absorbed by the leaves. 



Myrmecodia. — A pretty tale is that of Myrmecodia 

 tuberosa, a rubiaceous plant from the Malayan Archipelago. 

 The worthy Rumphius, still memorable as the pioneer 

 naturalist of these regions, " describes it in his Herbariiwi 

 Ainboyne7tse (1750) under the formidable but appropriate 

 name of Nidus germinans forinicariim rubrarum^ and 

 terms it '•'■ prodigmm ?iafiircB.^^ He seems to have been 

 uncertain whether the whole was a vegetable, or whether 

 the tuber was an ant's nest from which the plant sprung ; 

 he says it is to be regarded as a zoophyte among vege- 

 tables ! It presents the form of a large irregular tuber 

 growing on the branches of old trees ; from this spring a 

 few thick fleshy stems, having a small number of smooth, 

 leathery, oblong leaves crowded together at their summits. 

 The small white sessile flowers are situated at the base of 

 the petioles, and almost concealed by the large persistent 

 stipules. The tuber is tenanted by small and very fierce 

 red ants, which rush out upon the intruder if their dwelling 

 is attacked. The way in which these ants take possession 

 of the Myrmecodia, and the intimate relation which exists 

 between the plant and the insect, are thus deferred to in 

 Professor Camel's recent paper upon the genus.i The 



1 Nuovo Giornale Botanico Italiano, iv, pp. 170-176 (1872), 



