CLASS GVNANDRIA. 179 



a notch at its extremity, this sac or cavity is very 

 large, more resembling a bladder than a slipper, and 

 all the rest of the lip is merged in this part of the or- 

 gan, of which, however, there are still vestiges, and a 

 sort of spur at the base of the sac, in Cypripedium 

 arietimtm, and even 5 perfect petals. In the genus 

 Ophrys, as now limited, altogether exotic, the lip puts on 

 the most fantastic forms and colors, so as, with the rest 

 of the flower, to resemble different insects, such as 

 the Fly, the Bee, the Wasp, and the Spider, and in 

 another the rude form of a man suspended by the 

 head. The style in this family is never central, but 

 so inclined to one side as to resemble an upper Up to 

 the corolla. This organ in Orchis presents 2 lateral 

 sacs, in each of which are included a stipitate, clavate 

 (or club-shaped) mass of pollen agglutinated together. 

 In many other genera the masses of pollen (2, 4, or 8) 

 are inserted into the under side of an articulated move- 

 able lid, seated near, or upon the summit of the style. 

 The fruit is universally a 3-sided capsule, with 3 valves, 

 but only one cell, and filled with very many minute 

 seeds, of which extremely few are ever fertile. The 

 only example with which I am acquainted, where these 

 seeds are necessarily perfect, is in the very curious 

 Chiloglotlis of New-Holland, which, contrary to the 

 whole order besides, is only of an annual duration. 

 The tropical genera of the natural section Epidendra, 

 presenting a labyrinth of generic characters, or very 

 small groups, are remarkable for the beauty and vivid 

 coloring of their flowers, and the fantastic forms of the 

 ever varying 6th petal, or lip. From this tribe we 

 derive the Vanilla of commerce, which is the pod or 

 capsule of the Epidendron Vanilla. Salep is obtain- 

 ed from the roots of some of the species of Orchis ; 

 but, in general, the terrestrial plants of the Orchideje 

 are of such a rare and scattered occurrence, and con- 



