1884.] NATURAL SCIENCES OF PHILADELPHIA. 141 



American Association for the Advancement of Science^ p. 27 Y, 

 vol. xix, 1870, in which, contrary to the accepted hypothesis that 

 a fasciated branch was due to " over-luxuriance," or a high con- 

 dition of vitality, he showed that the result was due to a degra- 

 dation of vital power. A number of phenomena conceded to 

 result from low vital conditions, were shown to be inseparably 

 connected with fasciation, the essential feature of which is the 

 production of an extraordinary number of buds, with a corre- 

 sponding suppression of the normal internodal spaces. 



This is precisely the condition of a flowering branch ; and all 

 its attendant phenomena find their analogue in a fasciated stem. 

 Taking a composite flower in illustration — a sunflower, for 

 instance — we find on the receptacle a coil of many hundred florets, 

 each floret with a chafl"y scale at the base. Each of these florets 

 in morpholog}^ represents a branch, and the scale a leaf or bract, 

 from the axil of which the branch would have sprung. If we 

 imagine the head uncoiled, and everything in a normal vege- 

 tative condition, as distinct from the condition of inflorescence, 

 we might have a sunflower plant a hundred feet high or more. 

 But with the approach to the flowering stage we have a suppres- 

 sion of vegetative development, with a highly accelerated develop- 

 ment of buds, out of which are morphologized the floral parts. 



The receptacle on which the involucral scales and other parts 

 of inflorescence in a compound flower, had also its analogue in 

 the thickened stems which bore the buds in a fasciated branch. 



The phenomena which indicated low vital power in the fasciated 

 branch, were all manifested in a flower. Taking the test of vital 

 power as the ability to retain life under equal circumstances, we 

 find the leaves on a fasciated branch dying before those on the 

 rest of the tree. On the balsam fir, an evergreen, the leaves are 

 wholly deciduous ; or a deciduous ally, the larch, the leaves mature 

 before the others. On other trees we find always the leaves 

 enduring longer than those on the fasciated. We sa}' the leaves 

 on the latter have a lower vital power. In severe winters the 

 branches in the fasciation wholly die, in many cases, while those 

 on other portions of the tree survive, and again we say, because 

 they have a lower vital power. Precisely^ the same circumstances 

 attend inflorescence. The leaves in their procession from a 

 normal condition to petals lose this evidence of vitality in pro- 

 portion to the degree of transformation. The petal dies before 

 the sepal, the sepal before the bract, and the bract before the 

 leaves, in the general order of anthesia, in a compound flower, 

 though there are cases where, secondary causes coming into play, 

 this rule would be reversed, but, in a general way, the soundness 

 of the point would not be disputed. 



From all these facts in analog}- it might be said in addition to 

 the points brought out in the paper of 1870, above cited, that 

 a fasciated branch is an imperfect and precocious attempt to enter 

 on the flowering or reproductive stage. 



