ORCHIDACK^. 227 



ent to the stigma or style. There is also usually but a, 

 single stamen, of two rather widely separated anthers, hut 

 in the last genus of the following list there are 2 distinct 

 stamens, with the rudiment of a third at the back of the 

 stigma. As explained in Part I. , sections 90-93, the Orchids 

 as a rule require the aid of insects to convey the polUnia, or 

 pollen-masses, to the stigma, but occasionally it happens 

 that when the anther-cells burst open the pollinia fall for- 

 ward and dangle in front of the viscid stigma beneath, 

 being sooner or later driven against it either by the wind or 

 by the head of some insects in pursuit of honey. In all oases 

 where the student meets with an Orchid in flower, he should, 

 by experiment, endeavour to make himself acquainted with 

 the method of its fertilization. 



The Orchis family is a very large one, there being prob- 

 ably as many as 3,000 different species, but the greater 

 number are natives of tropical regions. Many of them are 

 epiphytes, or air-plants, deriving their support chiefly from 

 the moisture ot the air, through their long aerial roots 

 which never reach the ground. The perianth in many 

 species, and particularly the labellum, or lip, assumes the 

 most fantastic shapes, making the plants great favourites 

 for hot-house cultivation. In Canada the representatives of 

 this great Order, though not very numerous, are among the 

 most interesting and beautiful of our wild flowers. They 

 are, as a rule, bog. plants, and will be found in flower in 

 early summer. 



Synopsis of ttae Genera. 



* Anther only one,butof2 cells, these separated in the first genus, 

 .*- Lip with a spur underneath. Anther on the face of the stigma-. 



1. Orchis. The 3 sepals and 2 of the petals erect and arching over the 



centre of the flower ; the lip turned down. The 2 glands or viscid 

 disks of the base of the pollen-masses enclosed in a little pouch 

 just over the concave stigma. Leaves 2, large. Flowers few, in 

 ' a spike. 



2. Habena'rla. The lateral sepals usually spreading. The glands or 



viscid disks of the pollen-masses not enclosed in a covering. 

 Flowers in spikes. 



