156 MYSTERIES OF THE FLOWERS 



It is the rule, nearly absolute, among our native 

 orchids, that the ovary is twisted through 180 de- 

 grees and we find the external ribs or ridges de- 

 scribing spirals about them. The result of this 

 twist is that almost all the orchid flowers are actu- 

 ally inverted. Their upper petals have become the 

 lower lips, and for so many centuries have served 

 as lips and landing-stages for insects that these mis- 

 placed petals have taken on colours and form, chan- 

 nels and tufty beards, to fit them for the work they 

 have to perform. 



But the Calopogon and the Habenaria niva have 

 not thus turned their heads upside down, and in 

 these two we may, perhaps, find the earliest and 

 the latest development of our orchids. 



Southern White Small Orchis — Hahenaria nivea 



This rare and inconspicuous little orchid has a 

 remarkable and exceptional feature — its ovary is 

 seen to be noi'mal and the ridges upon its surface 

 straight and parallel. The spur, where nectar is 

 secreted, consequently lies above the ovary; and 

 the petal which usually forms the lip, here waves 

 as a banner above the nectar-well. 



In jNIr. Gibson's book on the orchids I read of 

 this flower and the insect's visit to it: 



"Perhaps there are some odd manners left over 



