CYPRIPEDIUM. 7 



The sepals are spreading; the upper or dorsal one is free, the lateral 

 two are connate to their apices,* and are together smaller than the 

 upper one, and lie under the labellum. 



The petals are also spreading, free, much narrower than the sepals, and 

 usually bearded at the base. 



The lip is inflated, calceiform, the lateral lobes at the base small and 

 turned inwards, their edges nearly meeting ; the inner surface opposite 

 the aperture is pubescent or setose, f 



The column is short and terete, pubescent, or studded with stiffish 

 erect hairs. 



The fertile anthers are two, one placed on each side of the column, 

 behind the stigmatic plate, and usually sessile ; the pollen is granulose, 

 but "coated by a viscid fluid, so glutinous that it can be drawn into 

 threads." 



Side and front view of sexual apparatus of Cypripedium barbatum : 

 a. anther ; st. staminode ; s. stigmatic plate. 



The third anther is reduced to a variously shaped barren 

 staminodium, forming a large apical plate, which, owing to the oblique 

 position of the column with respect to the ovary, conceals in most of the 

 species the fertile stamens and the stigma. 



The ovary is unilocular with parietal placentation, the rudimentary 

 ovules being placed along the parallel edges of each of three broad ribs. 

 The cajjsule is elongated, spindle-shaped, frequently angular. 

 In their vegetation, the tropical Cypripedes are perennial stemless 

 herbs with persistent foliage, increasing in size by lateral growths, 

 usually forming in their native haunts small tufts in the crevices 

 of the rocks, or in the forks of the branches of trees in the case 

 of those species that are more distinctly epiphytal ; but where the 

 food material is more abundant, forming larger patches that cover a 

 considerable space. 



* Sometimes (by dialysis) disjoined down to about one-third or even less of their length from 

 the base, a condition that is normal in Cypripedium arietinum, a foliose North American 

 species. This dialysis occurs chiefly in the first flowers produced by newly imported plants. 



+ The lip is distinctly three-lobed, the intermediate lobe greatly exceeding in size the lateral 

 two. The slipper or pouch is formed chiefly by the large middle lobe, whose sides are folded 

 over and joined together at the edges, the suture or line of junction being distinctly perceptible 

 in nearly all the species. It is evident that, owing to this peculiarity, it is really the under 

 (dorsal) surface of the labellum that is exposed to view, and which in most orchids is usually 

 of a very dull colour compared with the brilliant hues of the upper (ventral) surface. If the 

 pouch be cut down the suture so as to expose to view what is really the upper surface of the 

 labellum, it will be found that in many species this is also the brightest coloured, especially 

 the central and basal area, to which the light has access. 



