157 



STRASBURGER'S NEW INVESTIGATIONS ON THE 

 PROCESS OF FERTILISATION IN 

 PHANEROGAMS. 



By THOMAS HICK, B.A., B.Sc, 

 President of the Botanical Section of the Yorkshire Naturalists Union. 



There are few men who have done more for the advancement of 

 botanical science during the last few years than the eminent Professor 

 of Botany at the University of Bonn. The industry which he 

 displays is as rare as it is exemplary, and is deserving of the 

 grateful appreciation of all students of the science. His skill in the 

 work of practical investigation is such as can only be described as 

 ingenuity of the highest type, while his perception of the bearings 

 of the results obtained upon biological problems yet unsolved, rises 

 at times to the height of genius. 



The latest addition to the list of his publications ('Neue 

 Untersuchungen iiber den Befruchtungsvorgang bei den Phanero- 

 gamen, als Grundlage fiir eine Theorie der Zeugung.' Von Dr. 

 Eduard Strasburger. Jena, 1884) is occupied with an account of 

 fresh investigations into the process of fertilisation in phanerogams, 

 as a basis for a theory of generation. That it is not less worthy of 

 the attention of physiological botanists than his previous works goes 

 without saying, and I therefore offer no apology for presenting a 

 brief resume of its contents to the botanical readers of the Naturalist. 

 It should be remarked, however, at the outset, that by the term 

 'fertilisation' as here used, the reader must not understand what is some- 

 times meant by it, viz., the deposition of pollen upon the stigma. 

 For this latter process the term ' pollination ' is now more accurately 

 employed, while by ' fertiHsation ' is meant the impregnation of the 

 oosphere, or egg, within the embryo-sac of the ovule. 



In the first section of his work, Strasburger deals with the 

 structure of pollen grains, and the phenomena attendant upon the 

 development of the pollen-tube. These grains were formerly 

 thought to be simple unicellular structures, but it is now generally 

 known that such is not always the case, except when first formed in 

 the pollen mother-cell. In Zaniia and Ceratozamia, as Juranyi has 

 shown, the originally one-celled pollen grain — distinguished as a 

 progamous cell — divides into a small vegetative cell, and a larger 

 progamous cell of the second order. In Zajnia^ the latter again 

 divides into a larger generative cell and a second smaller vegetative 

 cell, while in Ceratozamia the differentiation is not complete until a 

 third vegetative cell has been cut off. The two or three vegetative 



Feb. 1885. 



