Osyris, Loranthus and Viscum. 185 



seed from a cell of the parenchyma of a part of the ovarium, we need not be 

 staggered by assuming that the male influence of A 'nthoceros, and possibly of 

 Ferns, causes the development of the organs of reproduction from the paren- 

 chyma of the frond at a distance from the point to which the male influence 

 is first applied. And this argument will, I think, be a good deal strengthened 

 if the usually-adopted notions of an "ovarium infer um" be so explained by in- 

 vestigation as to refer the part of the ovarium of Viscum, in which the embryo- 

 nary sac becomes developed, to the axis, which,! believe, is M. Schleiden's 

 view of its nature. 



The second, even if it be established as resulting from the excessively slow 

 travelling of the end of the pollen tube, will tend to show that there need be 

 nothing at all contemporaneous between the occurrence of fecundation, as 

 shown by the stigmatic changes, and its results. And this, taken in con- 

 junction with the fact that the ovulum of Osyris does not enter into the com- 

 position of the seed, and is unchanged by fecundation, may, I think, be 

 legitimately made applicable to the explanation of the phenomena presented 

 by Mosses subsequently to fecundation. I think also that it materially 

 weakens the arguments which, in conformity with perhaps arbitrary notions 

 of the necessity of immediate relations as to time in the fecundation of these 

 plants, require the sexes to be sought for in the capsule*, and those which with 

 more reason might have been urged from the ovulum itself suffering compara- 

 tively no change. 



2. Reduction of an Ovulum to the Nucleus. 

 The non-development of either of the ordinary integuments of the ovulum, 

 that is, the reduction of this to the nucleus, was, so far as I know, first observed 

 by M. Adolphe Brongniart in Tkesium ; and this is the only point on which 

 the observations of this distinguished botanist agree with the later ones of 

 M. Decaisnef. This sort of reduction or suppression is now known not to be 



* See Mr. Valentine " on the Development of the Theca and on the Sexes of Mosses," Linn. 

 Trans, vol. xvii. p. 477. 



t So different are these two accounts, both of which are illustrated, that it appears evident that 

 two observers, having one and the same object sub oculis, may represent it in two very different, and 

 indeed opposite manners, or that the sports of nature are not always confined to form. If this latter 

 be the case, my ideas of structure will be almost as much shaken as my ideas of many of the usually 

 adopted Orchideous generic forms have been by the celebrated variations of Monacanthus. 



