62 



SOME SOUTH !\DI.\\ INSEl fS I D [CHAP. VII. 



It is impossible t<> attempt to narrate here the various adapta- 

 tions in both insects and plants by which cross-fertilisation is 

 secured but we may note in passing the curious fly-trap formed by 



' -Section of Aristolochia, a flower which attracts flies. These are able 

 to entei '"it not t" escape owing t" the inwardly directed hairs of the 

 perianth tube. Alt. i tin anthers have dehisced, these hairs shrivel and 

 ipe. ' After Knuth.) 



Aristolochia, into which small flies are attracted and imprisoned 



until the pollen is ripe when they are again released, and the 

 methods by which the pollinia of Asclepiads and Orchids are 



Head ol Sphingid Moth with two Pollinia to the lefteye. 



1 ii iginal.) 



attached to the legs or heads of insect visitors thereby ensuring a 

 dispersal of pollen to the plants visited afterwards. There is a 

 nd almost untrodden field in India tor anyone who will take 

 up the Study of the pollination of flowers by different animals 

 (insects, birds, bats, etc.). In various tropical regions, notably in 

 South America, there are found plants which are inhabited by 

 ants to whose use thej are perhaps specially modified. These 

 plants have usually hollow thorns or internodes, admirabl) adapted 

 as nesting-places lor ants which bore into them, sometimes through 

 i spi , tally thin portion of the outer surface, and live in the spaces 



thus provided. In some cases the plants provide not only shelter 

 lor the ants but also secrete from special glands a sugary fluid 



