106 PROCEEDINGS OF THE ACADEMY OF 



MORPHOLOGY OF CARPEILARY SCALES IN LAEIX. 

 BY THOMAS MEEHAN. 



The facts which I have from time to time contributed, verbally 

 or in papers, to the Academy, in regard to longitudinal series of 

 axillary buds, and adnated and free leaves in coniferous plants, 

 will, I believe explain something of the structure of the flowers 

 of coniferse, which, if not quite distinct from any view before taken, 

 will at least have reached the conclusion by an original line of 

 argument. 



I have shown that in the cases where there are longitudinal series 

 of buds, one of the buds, and generally the upper supra-axillary 

 one, is the largest. So far as this longitudinal series of buds is 

 concerned, I find by extensive observation that there are very 

 few of our American trees or shrubs which do not produce them 

 under some circumstances, although they are more generally 

 apparent in some than in others. In many cases they do not 

 break quite through the cortical la3'er, but continue to grow from 

 year to year, just as the wood grows, always remaining just 

 under the outer bark. It is from these concealed but living buds 

 that the flowers of the Cercis. or the spines of Gleditschia, will 

 often appear from trunks many years old. In Magnolia and 

 Liriodendron these concealed buds are easily detected b^^ a thin 

 shave of the outer bark with a sharp knife. In very vigorous 

 shoots of the latter, a series of two — one supra-axillary — is not 

 rarely found prominently above the bark. In many cases one of 

 these buds, usually the lower, and really axillary one, never 

 pushes into growth. In Gymnocladus neither upper nor lower 

 would probably ever push, onl}^ for the fact that it matures no 

 terminal bud, and thus the laterals have to renew the next 

 season's growth. But for this, Gymnocladus would go up like a 

 palm, or, more familiarly, as Ar'alia spinosa does, without a 

 single branch. Failing in the terminal, but two laterals push, 

 giving the branches their dichotoraous character. The two which 

 push are always the upper ones in the series of 2, 3, or 4, which 

 appear in this species. 



The purpose of this duplication of axillary buds will interest 



[July 11 



