1020 



a length ; and this is the less necessary as the menioiv itself will 

 immediately appear in full in the Society's ' Transactions.' 



Under the head of" Development of the Embryo " the author gives 

 the following statement of his opinion on the question of impregnation, 

 and the mode in which it is effected : — " My opinion with regard to 

 the fertilization is, that the operation is effected by the contact of one 

 or more speniiatozoids with the mucilaginous filament contained in or 

 hanging from the month of the canal of the archegonium. 1 have 

 seen the spermalozoich swimming in numbers around the mouths of 

 archegonia, but never detected one inside, and I do not see any good 

 reason for supposing such a process necessary. The pollen-tube of 

 flowering plants only comes in contact with the outside of the embryo- 

 sac, and the influence is sometimes communicated through a long 

 suspensor ; and there does not seem to be any sufficient objection to 

 the supposition, that the contact of the spermatozoid with the filament 

 of mucilage which lies in the canal of the archegonium, suffices to 

 convey the necessary stimulus. I imagine this stimulus resides in the 

 mucilaginous fluid in which the spermatozoid is bathed in the sperm- 

 cell, and which, adhering to this, is conveyed to the mucilage (proto- 

 plasm) of the germinal vesicle, ^just as the contents of the pollen-grain 

 become combined with the protoplasm of the germinal vesicle in 

 flowering plants. The nature of the process is clearly a problem 

 beyond the reach of science, but it seems to me a necessary induction 

 fiom the facts in the Phanerogamia, that the phenomena result there 

 from the material union of two fluids, and I hence conclude that this 

 is the case here. The comparatively few cases of successful impreg- 

 nation among these prothallia, so many of which prove sterile, may 

 perhaps be accounted for by the peculiar conjunction of circumstances 

 required to bring a sufficient amount of the fertilizing fluid, by means 

 of the spermatozoidsy to the germinal vesicle, at the precise epoch 

 required." 



His general "conclusions" areas follows: — "In summing up all 

 these statements it becomes evident that the balance of evidence is in 

 favour of the existence of sexual organs, and of a process of impreg- 

 nation, giving rise to a new individual, as asserted by Suminski, 

 although under conditions somewhat different from those described 

 by that author Only two of the observers who have repeated his 

 investigations throw doubt upon these points, namely, Wigand and 

 Schacht ; the statements of the former as to matters of fact are far 

 from sufficient to bear out the mass of argument he has built upon 

 them against the existence of sexes ; in fact, his observations were so 



