32 



GENERAL REVIEW OF THE ORCHIUE.^. 



l)ui one (in superficial inspection ; this will hv cxplaiiicA in the next 

 scctidn, which is devoted to the homologies of orchid tlowers, but 

 ■without that assistance the presence of all three is easily detected in 

 Cypripediuni, in which the stigmatic plate is divided into three 

 equal parts by lines diverging from each other at an angle of 120° ; 

 each of these parts represents a stigma and is callable of performing 

 the proper functions of that organ. In the other tribes the lower 

 two of the three are confluent and form the cavity in front of the 

 labellum, in which the poUinia are deposited when the flower is 

 fertilised. The third or ujiper one is modified into a remarkable 

 organ called the rosteUu/n, of which nothing like or analogous to it 

 exists in the flower of any other family of plants. Like the other 



Capsule of Odontoglossuui maxillare. 

 (From the Gardeners' ChronicJe.) 



Capsule ot Peiisteiia pcndula, 



after dehiscence. 



(From the Gardeners' Chruaide) 



parts of an orchid flower the rostellum presents "a marvellous amount 

 of diversity of structure in the several tribes." 



The capsule or fruit which contains the seed varies greatly in size 



and form, not only in the different genera, but also in the same 



genus when it is an extensive one as Dendrobium, jNIasdevallia and 



Odontoglossum. The accompanying illustrations will convey an accurate 



idea of the various forms of some of the capsules. 



The surprising diversity in the form and aspect of orchid flowers 



described in the foregoing pages is still further exemplified in our 



native orchids, and especially in many Australian and South African 



genera as Caladina, Corysanthes, Dipodiumj Thelymitra, Holothrix, 



Satyrium, Pterygodium, etc., etc. 



