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growth. In other words, a line of separation is made at the base 

 of the leaflet so that in its going it may not disturb the others 

 that are situated close by and all at the upper extremity of the 

 petiole. There is no disputing the convenience of this in the 

 plant economy to the lame and lazy, for the injured and indolent 

 may sever their connection and drift down the hedge-row, while 

 their fellows, still green perhaps, stay longer for the finishing 

 touches, and until the vital fluids may be withdrawn under cover 

 of gorgeous decay. 



Turning again to the "simple-leaved ampelopsis," with which 

 we started, it is found that the same arrangement is made for the 

 fall of the foliage. The joint is formed at the base of the blade 

 and when the latter falls there remain the stiff petioles for some 

 time to come. Why this double provision for the release of the 

 leaf— first a well-formed suture at the base of the blade and an- 

 other at the union of petiole with the branch ? In other words, 

 why does not this leaf, in form like a linden, observe the method 

 of the linden, or the maple, or the oak ? Shall we find an answer 

 in a study of kinship ? Because its sister, the " pepper-vine " 

 \Anipelopsis arborea (L.)] , of the South has compound (bipinnate) 

 leaves and sheds them piece-meal, is that any reason why my 

 A. cor data should do the same so far as it can ? Its half-sister, 

 the American ivy, we have seen, does likewise, although its 

 leaves are compounded upon a different pattern from those of the 

 "pepper-vine." When we come to look at the Japanese ivy 

 \Parthenocissus tricuspidata (Sieb. & Zucc.)] with its leaf-blades 

 only three-lobed usually, but sometimes three-divided, it is found 

 that the same method obtains, and my neighbor's outside chim- 

 ney has' at first a leaf-shingled surface of green, then is splashed 

 with purple, followed by a showing of stiff upturned "straws " 

 and the bricks beneath. It is a little family trait and whether 

 there be one or many leaflets to the blade, the parting with the 

 mother parent is the same. 



If the several species were once all in one it is possible that 

 that one had compound leaves and defoliated by means, natural to 

 such leaves. Then in the passing of the years the " simple- 

 leaved ampelopsis " has acquired the present form by enlarging 



