Structure and Division of the Vegetable Cell. 217 



structure and division have also been verified in Cbara, an 

 account of which will be given in a future paper. 



These investigations have been carried on in the Botanical 

 Laboratory of the University under the direction of Pro- 

 fessor Dickson. I am indebted to Mr Geddes for various 

 kind helps readily given, to Professor I. B. Balfour of Glasgow 

 for explanations and references, and last, though perhaps not 

 least, to Mr Sadler, for liberty to obtain fresh specimens, 

 which have been plentifully supplied to me by Mr Lindsay. 



The Society's thanks are due to Mr Kidston, for his faith- 

 ful transference to stone of the drawings which make up 

 Plates IX. and X. 



EXPLAXATIOX OF PLA.TES. 



Plate IX. — Figs. 1-3. Epidermis of Ornithogalura pyramidale, 

 X 400. Fig. 3 is a patch of cells which show not only normal 

 stoma phases, but also several interesting from a teratological and 

 pathological aspect. 



Figs. 4-8. Cells from epidermis of Scilla hifolia, x 900, showing 

 successive division of the nucleolo-nucleus, nucleolus, and nucleus 

 of the stoma mother cell In fig. 8 the nucleoU of each daughter 

 nucleus have re-divided. 



Figs. 9-11. Cells from epidermis of Scilla hifolia, showing divi- 

 sion of the ordinary epidermal cells, x 450. 



Figs. 12 and 13. Parenchyma cells from leaf of Ornithogalum 

 pyramidale, x 400. 



Figs. 14 and 15. Parenchyma cells from leaf of Ornithogalum 

 pyramidale, x 900. Explanation in text, p. 200, 



Figs. 16-20. Ordinary epidermal cells from rather old leaf of 

 Ornithogalura pyramidale. Stages in division of the nucleolus ; the 

 process not proceeding further. The nucleus exhibits a very clear 

 nuclear membrane and intranuclear network. 



Figs. 21-29. Fundamental tissue-ceUs of Equisetum limosum 

 dividing. Explanation in text, x 400. 



Plate X, — Fig. 1. Single cell from filament of Spirogyra nitida. 

 This one is exceptionally large, having been drawn in winter when 

 many seem to have a tendency to extreme elongation without divi- 

 sion. The filaments connecting the nucleus with the chlorophyll 

 bands are very evident. 



Fig. 2, Sragle cell from filament of Spirogyra nitida. The nucleus 

 alone is represented as showing the eiiect of endosmosis on it. 



