742 Mr. Brown on the Organs and Mode of 



does not however extend to their gradual increase and progress, 

 both of which may be absolutely ascertained. 



Jn Bonatea they are, in the first stage of their production, 

 confined to the stigma, with the proper tissue of which they are 

 more or less mixed. Soon after they may be found on the an- 

 terior protected surface of the style, at first in small numbers ; 

 but gradually increasing, they form a mucous cord of consider- 

 able size, in which very few or none of the utriculi of the stigma 

 are observable. This cord, which is originally limited to the 

 style, begins, though sometimes not until several days have 

 elapsed, to appear in the cavity of the ovarium, where it divides 

 and subdivides in the manner I have described in my paper, its 

 descent being gradual until the cords nearly equal the length 

 of the placenta, to which they are parallel and approximated. 



That these cords are not in any degree derived from those 

 portions of the walls of the cavity of the ovarium, to which they 

 are closely applied, and which I have termed the conducting 

 surfaces, is manifest from the identity in state of those sur- 

 faces before and after the production of the cords. 



In Bonatea the first evidence of the action of the pollen con- 

 sists in the withering of the stigma ; a similar decay of the 

 greater part of the style soon follows, and the enlargement of 

 the ovarium generally begins before the withering of the style 

 is completed. When the enlargement of the ovarium is consi- 

 derable, and the mucous cords are carefully formed in its cavity, 

 a corresponding enlargement of the ovula takes place, and the 

 nucleus becomes first visible. 



I have no satisfactory observations in Bonatea respecting any 

 tubes going oft" from these cords and mixing with the ovula ; 

 but in Orchis Morio 1 have repeatedly and very clearly observed 

 them scattered in every part of the surface of the placenta, and 

 in not a few cases have been able to trace them into the aper- 

 ture 



