On the development of the Spora of Anlhoceros Icevis. 93 



depressions in the tender substance of the mother-cellule 

 when the membrane of the sporae is covered with granules 

 or little pointed eminences (de granules ou de piquans,) 

 we shall find simple cavities corresponding to these in the 

 mother-cellule ; when the former is covered with a fibrous 

 network we see corresponding to this pentahexagonous pro- 

 longations of the mother-cellule, passing into depressions 

 in the form of alveoli of the membrane of the sporae, and 

 imparting to the membrane of the mother-cellule, when we 

 separate it, a tessellated aspect. This is well seen in the 

 Riccia glauca. 



According to what I have mentioned above, it is very pro- 

 bable that the membrane of the sporae is the production of 

 the mother-cellule, and, as it were, a hardened secretion of 

 this latter, it appears rather to draw its origin from the con- 

 densation of the mucilaginous and granular substance above 

 described, and that the mother-cellule only appears to de- 

 termine the form of the membrane of the sporae. 



This seems to me to be proved not only from the develop- 

 ment of the Anthoceros just as I have described it, but I am 

 solicitous to intimate in this place the analogy in the sporae 

 of the inferior Cryptogamae, for example, that of certain Con- 

 fervas, as the Zygnema, in which the membrane of the sporae 

 is formed around an accumulation of granules, which is less 

 than the volume of the cellule, and in which consequently 

 the membrane of the sporae is in no way applied to the wall 

 of the cellule. 



When in fine, as to the separation of the mother-cellule 

 into four distinct cellules, each of which contains a spora, 

 which according to M. de Mirbel will form the distinctive 

 character between the mother-cellules of the spora and 

 those of the pollenic grains, I am of opinion that it is not 

 observed in all the mother-cellules of the sporae, but that, in 

 plants nearly allied, sometimes it takes place and sometimes 

 it does not. I have not succeeded in observing it in the An- 



