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VOLUME XXIV NUMBER 4 
POXOPANICAL G5AZEPRE 
OCTOBER 1897 
NOTES ON THE FECUNDATION OF ZAMIA AND THE 
POLLEN TUBE APPARATUS OF GINKGO. 
HERBERT J. WEBBER. 
(WITH PLATE X) 
A PRELIMINARY discussion of the development of the pollen 
tube apparatus' and the antherozoids? of Zamia was given by 
the writer in the June and July numbers of this journal. The 
object of the present preliminary paper is to call attention to 
some of the peculiar phenomena which occur during the process 
of fecundation in Zamia, and to certain features in the develop- 
ment of the pollen tube apparatus of Ginkgo, in which further 
light is thrown on the origin of the centrosome-like body occur- 
ring here as in Zamia. 
For a considerable time during the development of the 
pollen tube apparatus in Zamia the archegonium remains in 
nearly the same stage of development, simply increasing gradu- 
ally in size. During this period the very large nucleus remains 
at the apex of the archegonium as figured by Treub in Cycas 
circinalis 3 Shortly before fecundation this nucleus divides, and 
* Peculiar structures occurring in the pollen tube of Zamia. Bort. Gaz. 23: 453- 
June 1897 
* The development of the antherozoids of Zamia. Bot. Gaz. 24:16. July 1897. 
M vevoneaann sur les Cycadées. Ann. du Jardin Bot. de Buitenzorg 4: pl. 2. 
1897] 225 
