122 peesident's addeess. 



contains one or more Nuclei, each with its Nucleolus. This 

 nucleolus is the very citadel of life, the nucleus is its castle, the 

 surrounding protoplasm its commissariat, and may be skirmishers 

 as well as foragers. A word or two on cell growth, and especi- 

 ally on free-cells. The fundamental unit of every organic body 

 is a cell. Therefore the simplest living being is a single free- 

 cell. The highest animal or vegetable is simply an aggregation 

 of cells. 



Pollen grains always consist of isolated cells. Free-cell forma- 

 tion does not usually occur in ordinary vegetable growth but 

 is intimately connected with reproduction, and is therefore 

 well seen in the growth of pollen and of its allies, Swarmo- 

 spheres, Antherozoids, etc. The Swarmospheres of the Algse are 

 primordial cells, that is naked protoplasm, as are the Anthero- 

 zoids of Cryptogams. The Antherozoids are endowed with 

 motion, and so reach and fertilize the Zoospheres or Spermato- 

 zoids. In the higher Cryptogams the Microspores represent the 

 pollen of the Phanerogams, as do the Macrospores the ovules. 

 The Sporangium of a Vascular Cryptogam therefore answers to 

 the Pollen-sac of a Phanerogam. It is a pretty sight to watch 

 the antics of the brown Antheridse or spores of Equisetum 

 arvense as they are being examined under the microscope. Each 

 spore is furnished with four elators, eminently hygroscopic, and 

 therefore every breath of the observer causes the spores to leap 

 about the glass slip. PL 4, f. 31. 



As the Phanerogams embrace both Grymnosperms and Angio- 

 sperms, the Gymnosperms forming the link between Cryptogams 

 and Angiosperms, it will be seen that all Phanerogams are not 

 true pollen bearers, but only the Angiosperms. These include 

 all Monocotyledons and Dicotyledons, which are the true pollen 

 producers. 



The pollen they produce varies greatly in mode of production, 

 condition, grouping, shape, size, colour, and markings, but these 

 variations are astonishingly persistent, not only in species but in 

 genera and orders ; indeed, so much so, that the order or even 

 genus of a plant may in many cases be certainly known from an 

 examination of its pollen. Any marked departures may there- 



