STRUCTURE, 257 
To which variation is the greater amount of value to be 
ascribed? to the six carpellary structure of Vanilla, or the 
tricarpellary of Apostasia, in which last the carpellary leaves 
are opposite to the sepals?. Can the order of suppression 
enter in any manner into our notions of oscillation ? 
L j Sepals, 
2. ņPetals. | 
3. { Stam. 
4. Stam. barren. 
5. Barren carpells. 
6. Fertile do. 
One of the most conclusive arguments against the idea of 
the ovarium of an Orchideous plant being composed of 6, 
is the fact that no more than three stigmata have ever been 
observed. And on this head I may remark that the stigmata 
is the last portion of the carpellary leaf to become, so to speak, 
absorbed. We have many instances of an apparently simple 
ovary with more than one style or stigma, but no instance is 
known of a simple stigma existing with a really compound 
ovary. 
From Mr. Bauer's drawing it would appear that in Apostasia 
the lateral stamens are opposed to the lateral sepals. If 
this is correct the stamina and the stigmata are really opposed 
to each other.* 
1. Sepals. 
. Petals. 
Stamina. 
. . Carpella. 
To what extent can the anomalous situation of the placenta 
be explained ?. 
It is not difficult or absurd to imagine a carpellary leaf 
with a very stout midrib, and reduced lamina. 
Take away reduction in size of the cellular mass of a fertile 
SN CN 
* The structure of the anther of Apostasia is worth examining. 
H 2 
