STRUCTURE.] DEVELOPMENT OF PLACENTA. 387 



as the five stamens alternating with the divisions of the calyx, 

 and consequently opposite to those of the corolla. 



" The bud, therefore, possesses in this young state two of 

 its verticils, the calyx and the male apparatus. The latter is 

 already clearly enough marked, while nothing yet indicates 

 there the appearance of the corolla ; but from the time when 

 the stamens are developed into little distinct bodies, if the 

 calyx be removed, a slight swelling will easily be distinguished 

 at their origin, on the outer side, which swelling follows the 

 whole outline of their common base, and forms a well-marked 

 projection outside each of them. The slight swelling is the 

 nascent corolla, and the five little projections opposite to the 

 stamens are the five organic petals which compose it. 



"About the time when the corollary protuberance shows 

 itself on the exterior of the base of the young anthers, the 

 female organ begins to manifest itself as a kind of continuous 

 circular swelling, in the centre of which is perceived a small 

 rounded papilla. The swelling is the first indication of 

 the ovarian parietes, and the papilla the first sketch of the 

 placenta. At this period the young pistil organises and 

 developes its two portions equally. 



" The peripheric swelling, rising more and more, quickly 

 constitutes a kind of little utricle with rather thick walls, 

 truncated and open at the summit, while the placenta, elon- 

 gated and growing proportionally, forms a small ovoid body 

 which exactly fills the cavity of this young ovary, but without 

 exhibiting the slightest adhesion to its walls. In this state 

 it resembles a young solitary ovule. 



" A new modification now soon presents itself and becomes 

 more and more marked. The little ovarian utricle contracts 

 as it increases in length; thus its orifice in a short time 

 becomes elevated to the summit of a little truncated cone, 

 which is the commencement of the style. At the same time 

 the young placenta is a little contracted towards its free 

 extremity, so that its form is now turbinated, and its point 

 generally fills up the inferior opening of the styliferous 

 canal. Its surface, which until then had remained smooth, 

 quickly swells into little rounded papillae, which are the com- 

 mencement of the ovules. These ovules in Dodecatheon, 



c c 2 



