700 Mr. Brown on the Organs and Mode of 



me as made up of three simple ovaria united by their ovuli- 

 ferous margins ; a structure in which the ordinary relation of 

 stigmata to placentee is that here found. 



In Mr. Bauer's "Illustrations" already referred to, a very 

 different account is given of the composition of the ovarium, 

 which is there said to be formed of six pieces. 



This view of its composition seems to be founded on the 

 existence of six vascular cords, on the apparent interruptions 

 in the cellular tissue, and on the singular dehiscence of the 

 capsule. But the mere number of vascular cords, which, being 

 destined to supply all parts of the flower, may be said rather to 

 indicate the divisions of the perianthium than those of the ova- 

 rium, cannot be considered as affording an argument of much 

 importance, and, if it were, would equally apply to many other 

 families having trilocular ovaria, as Irideae ; while the inter- 

 ruptions or inequalities of cellular tissue may be viewed as only 

 the preparation for that dehiscence which, though very remark- 

 able in this order, is in a great degree analogous to that taking 

 place in most Cruciferae, in several Leguminosse, and in other 

 families of plants. It may also be objected to Mr. Bauer's view 

 of the composition of ovarium, that the arrangement of the 

 parietal placentae, which on this hypothesis would occupy the 

 axes of the three alternate component parts, is contrary to every 

 analogy ; while the position of the stigmata, if my account 

 should prove to be correct, affords evidence nearly conclusive 

 of the ovarium being formed of only three parts. 



In those genera of Orchideaj in which the lateral stamina are 

 perfect, and the middle stamen without anthera, namely, Cypri- 

 pedium and Apostasia, all these lobes or divisions of stigma are 

 equally developed, are of nearly similar form and texture, and, 

 as I have proved by direct experiment in Cypripedium, are all 

 equally capable of performing the proper function of the organ. 



In 



