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MB. S, LE M. MOORE S STUDIES 



Group I. (Immediate brown precipitate.) 



In the fundamental tissue of Musa sapientum run numerous 

 large tannin-sacs in the neighbourhood of and parallel to the 

 course of the vascular bundles *. Nessler's fluid immediately 

 turns this tannin a fine rich brown. 



Epiderm (upper and lower) of leaf of common Primrose. 

 Numerous tannin idioblasts are scattered among the ordinary cells, 



with 



JRosa canina. The 



,pical 



meristem of the stem are richly provided with tannin imme- 

 diately giving the brown colour. The same is the case with the 

 garden Eose. 



Epiderm of Grevillea robust a. Tannin occurs plentifully in 

 the cells overlying the vascular bundles on the lower side of the 

 leaf, also in a few cells in their immediate neighbourhood : else- 

 where tannin is restricted to the two subsidiary cells which lie on 

 each side of the stomatal guard-cells. 













Group II. (Yellow colour, changing through red-brown to 

 brown.) 

 A good example of the occurrence of this kind of tannin is the 

 fundamental tissue of the young stem of Aucuba japonica. At 

 first the colour is a pronounced yellow ; but in a few minutes 

 this gives place to brick-red, which is itself supplanted by a warm 

 brown. After a few days in glycerine, the colour of the tannin- 

 precipitate in such a preparation changes to a cold brown. 



Group III. (Eeadily diffusible yellow colour.) 



_* 



Thi 



the following : 



As instances, may be cited 



Leaf-scales of scape of Petasites vulgaris and Tussilago 



Farft 



vy. Fundamental tissue of young stem and the large stellate 



hairs clothing it. 

 Dandelion. 



underground 



Potentilla Anserina. Hairs thickly covering the plant 



canina 













* De Bary, Vergl. Anat. p. 160 (Engl, trend, p. 153). 





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