47 



this is the difficulty of obtaining Gnetum-material in the right 

 stages in sufficient quantity. I, for one, think it absolutely 

 necessary to be a resident in the tropics, if one wants to 

 obtain a pretty complete series and even then it is slow and 

 difficult work. Being a resident I resolved, to try what I 

 could do and this contribution is the first result of it. A 

 later contribution will have to treat the finer nuclear struc- 

 tures, the question of the possible presence of spermatozoa 

 in Gnetum Gnemon etc. It was found during this investiga- 

 tion that these points could only be settled by artificial polli- 

 nation of a female Gnetum-Gnemon and I am therefore doing 

 this during my rare holidays. 



I propose further to give papers on Gnetum mollucanum 

 Krst., the material of which has been pretty nearly all col- 

 lected and on which some considerable work has allready been 

 done and on Gnetum Ula Brongn., work on which had to be 

 stopped for this year as a disease, destroying the nucellus 

 was so vehement that after a certain stage not a single healthy 

 specimen could be obtained. 



I am now, by good fortune able to give a complete series 

 of I think, all, as yet undescribed stages of the grosser Mor- 

 phology of Gnetum Gnemon. It is a great pity that Karsten 

 did not obtain this species in the right stages, as the facts of 

 the development are here much clearer and more easily inter- 

 preted than in any of tlie species observed by him; that Kar- 

 sten, after having recognised the mistakes of his first paper, 

 interpreted the facts [obtained with rather scanty material] so 

 well in his second paper is certainly admirable. 



The reason that Karsten did not consider Gnetum Gnemon 

 L. a fit species to work upon as well as the circumstance that 

 this series has not been obtained by others at a much earlier 

 date is, as will be seen, due to the unfortunate circumstance 

 that in the Botanic Gardens at Buitenzorg there are only a 

 couple of female trees, so that the material received for ex- 

 ample by Strasburger through the kindness of the late Dr. 

 ScHEFFER was uot fertilised. 



