36 PROCEEDINGS OF THE ACADEMY OP 



edulis. I have shown already, in the paper before referred to, 

 that Thujopsis borealis ( Chamsecyparis, Nutksensis, Spach.) also 

 throws out free leaves always in the weakened cutting state. In 

 some garden varieties of Thuja and Biota the weak axis of the 

 seedling condition remains throughout many succeeding j-ears of 

 growth. In all these cases the leaves are free. These free leaved 

 forms are still regarded by some excellent European botanists as 

 species of unknown introduction, although, as stated in my paper 

 on u Adnation in Conifera," their derivation from Thuja and Biota 

 is founded on direct evidence. I refer to this incidental matter 

 chiefly to add the new observation, in connection with the leading 

 points of the present paper, that with their weakened condition, 

 the regular numerical order of branching, as noted in the fully 

 developed forms, does not exist. 



I do not suppose this law of vital vigor so far as developed will 

 account for all the phenomena of free or adnated leaves; or for 

 all the numerical relations of branchlets to the nodes. I have 

 myself pointed out some apparent exceptions, but I trust I have 

 made it clear that it performs no mean part in the order of these 

 things. 



[June 25, 



