26 



dark color, therefore ferric chloride may be employed for its 

 detection. 



LiGNlN.— Carbolic acid dissolved in concentrated hydro- 

 chloric acid gives a green color with lignin, and hydrochloric 

 acid and alcohol develop a beautiful rose color after some* 

 hours. 



The works most frequently consulted for methods in the 

 studies contained in this paper have been " Behren's Guide to 

 the Microscope in Botany/' by Hervey, and *' Goodale's 

 Physiological Botany." Upon the general subject much 

 assistance can be obtained from *' Sach's Vegetable Phy- 

 siology/' " Vine's Physiology of Plants/' and '* Strasburger's 

 Das Botanische Practicum/' The most elaborate paper con- 

 sulted is a '' Memoire sur la Moelle des Plantes Ligneuses/' 

 with numerous elegant plates, by A. Oris, in " Nouvelle 

 Archives du Museum d'Histoire Naturelle, 1870." 



I 



Rutgers College, 



July 2 1 St, 1890. 



) 



1 





