112 PLANTS OF NEW ZEALAND 



pollen grains are collected together into a few club-shaped 

 masses termed pollinia. These are often provided with a 

 small glutinous pedicel, by which they may be strongly 

 cemented to any object with which they come in contact. 

 The ovary is inferior, : (and in this respect therefore unlike that 

 of the lilies), and produces numerous minute seeds. 



Pollination of Orchids. 



Though most of the orchids require cross-pollination, and 

 many have elaborate devices to secure it, yet if these fail, 

 some of the species can be pollinated from their own anthers. 

 Many Orchid flowers remain open for a long time. Thus the 

 flower of one species of Cypripedium is said to last forty days, 

 and of another, seventy days. This would seem to suggest 

 that insect visits to these species are few and far between. 

 Mr. G. M. Thomson also remarks on the infrequency of insect 

 visits to those New Zealand orchids which he examined, though 

 he attributes this,* in part at any rate, to the general cold- 

 ness of the previous season. In spite of all their lures, 

 therefore, even the orchids at times are compelled to 

 resort to self-pollination. It is impossible to do more than 

 mention one or two of the more extraordinary devices, by means 

 -of which cross-pollination is secured amongst foreign orchids. 

 We will then give a short account of the methods adopted by 

 New Zealand forms. Perhaps the mode of pollination adopted 

 by Coryanthes, as described by Dr. Criiger, is one of the most 

 extraordinary.! 



" This orchid has part of its labellum or lower lip hollowed 

 out into a great bucket, into which drops of almost pure water 

 fall from two secreting horns which stand above it, and when 

 the bucket is half -full, the water overflows by a spout on one 

 ;side. The basal part of the labellum stands over the bucket, 



"Trans. Vol. XI. 11, p. 418 



fDarwin, Origin of Species, Sixth Edition, pp. 154-155. 



