110 PROCEEDINGS OF THE ACADEMY OF 



finally erect, as in tlic case of the willow catkin. He thought we 

 might safely conclude from these facts that vegetation not only 

 grew towards the light, but exercised at the same time a lifting 

 ibrce which we had not before recognized. 



He believed no explanation had ever been given that was 

 generally accepted as to the curving of many kinds of pine-cones. 

 Possibly the facts now offered might furnish the ke3\ 



Mr. Meehan then exhibited some expanding buds of Fraxinua 

 qjiadravgulata^aud showed that the}^ had no bud-scales as other 

 species of ash had. These other species had two pairs, the outer 

 broad and somewhat thin, and which underwent little change in 

 spring ; the other and inner often grew into a short succulent sub- 

 petiole. In the F. quadranrjxdata^ at the termination of its full 

 growth, instead of the usual broad scales, there were but minute 

 black specks, whi(;h in the spring grew out into fully developed 

 leaves. The buds of this species of ash were, therefore, "naked" 

 buds. He had under his observation only one tree of this kind; 

 but he took it lor granted it was the usual condition of other trees 

 of the species. 



On his grounds were man}' hundred of Fraxinus excelsior, and 

 lie noted this season a large number of them, of whieh he exhi- 

 bited specimens, that had the same characteristic buds as in the F. 

 quadrangulata. Examining further, he found that in all cases of 

 this kind the buds terminated second growths of last year. In 

 all other cases, where the normal solitary cycle of growth was all 

 that was made, the usual broad bud-scales were present. Thus 

 we arrived at the important conclusion that a law which operated 

 with sufficient uniformit}^ in the case of F. quadrangulata to con- 

 stitute a specific character, existed onlj- in special cases in another 

 species. What that law is, he thought 3'et unknown. To most 

 persons it Avould be a sufficient answer to say, it was the late 

 second growth which caused the non-development of true bud-scales 

 in the case of the F. excelsior ; but, remembering the case of i^. 

 quadrangulata, where the same facts existed without the second 

 growth, we could onl}- say that tliis circumstance merely aided 

 the action of a law, which could operate without it. 



He suggested that the science of botany had suff'ered from the 

 too hasty assumption of explanation of facts. For instance, it 

 was taught in our best text-books that the " office of bud-scales 

 was to protect the tender parts beneath." It would strike any 

 one at once that it ought to be as necessar}' for F. quadrangulata 

 to have this protection as F. excelsior ; but not ox\\y this, but 

 here we have the fact of F. excelsior getting through the winter 

 as well without as with them, and that, too, on the secondary, 

 and as man}- would suppose more immature, growth. 



Mr. Meehan further referred to a paper which he contributed to 

 the " Proceedings" of the Academy last fall, on the floAvers of 

 Ambrosia artemisiaefolia, in which he showed tliat the horns of the 



[July 11 



