186 Excerpta Botanica. 



tive colourless cellules, which still form the greater portion 

 of the mass ; other cellules, of a grey or yellow colour, in 

 the vicinity of the lacunae, of which they constitute the ^valls, 

 and chiefly remarkable by the presence of a central nucleus ; 

 and those larger cellules which fill the lacunae, and which 

 are identical with the utricules termed polliniferous by 

 Mirbel. 



These transparent utricules soon become obscured by the 

 presence of numerous granules, in the midst of which are 

 observed one or two bodies, likewise granular, but consider- 

 ably larger, which we shall term nuclei {noijaux). These 

 granules become gradually collected into a single mass in the 

 centre of the utricule, which is thus rendered more opake 

 in the centre, though still transparent through the increased 

 thickness of its circumference. This mass may with care be 

 abstracted entire from the cavity in which it is enclosed, 

 M"hen the nuclei will be found united, and at the end of some 

 days four may be distinguished. 



After the lapse of some time we perceive nothing more than 

 these nuclei, the absorbed granules having disappeared. The 

 nuclei are only separated by matter which at first is fluid, but 

 subsequently becomes solidified, and their form is that of so 

 many separate cells. During this same time, this matter be- 

 comes equally solidified on the interior walls of the utricule, so 

 as to form a thickening, which is apparently the result of many 

 successive layers, and its transparence becomes altered. Such 

 is the state of the anther about four months after the appear- 

 ance of the bud, when it exhibits on its internal face a consi- 

 derable number of small cells, which are merely closed by 

 the epidermis which extends over their apertures. In each 

 of these cells are pollinic utricules, with thick succulent walls, 

 marked with concentric zones, their internal cavity divided 

 by thinner walls into four still smaller cavities, containing as 

 many granular nuclei, which, on the rupture of their envelope 

 under Mater, escape. 



These latter nuclei continue to grow, become round and 

 invested with a yellow papillose integument, and with their 

 growth the walls and divisions of the utricules gradually 

 diminish and finally disappear, when the nuclei of the dif- 

 ferent utricules are found all free together in the common 

 cavity previously occupied by the polliniferous utricules ; in 

 short, they become so many grains of pollen in one of the 

 cells of the anther. From this time these grains assume that 

 external appearance which they ever afterwards retain, al- 

 though not yet arrived at their complete development, which 

 still goes forward in their interior. If by a slight pressure 

 we burst one of them, the nucleus issues forth, together with 



