INEQUILATERAL LEAVES. 575 
while those of the Northern prickly ash, of the same genus, are 
usually fuller on the lower side. Rhus toxicodendron has the lower 
edge of the side leaflets fuller; Rhus copalina has the upper edge 
fuller. For some time, I thought as De Candolle wrote (though 
I had not then read his book on the subject), that the unequal 
lobed leaves were all alternate ; and further, I thought they were 
all two ranked along the stem, and thus set off against each 
other, as leaflets in a compound leaf. I was not 
much surprised, however, though much interested 
to find that the opposite leaves of Cornus Florida 
were fuller on the lower edge, as they were all 
turned horizontally on the side branches. On the 
4th of July, the two terminal leaves were about half 
i grown and generally equal lobed at the base, though 
Two opposite not always so. I find the opposite leaves of several 
leaves of Eu- A i F 
phorbia, mac. of our Euphorbias, as noticed in Gray’s manual, are 
on the lower fuller at the lower edge as they are turned down 
horizontally. In a somewhat similar manner are 
the two parts of the involucre of Carpinus Americana. These 
stand with the fuller edge away from the axis. The two edges 
of each are unequally serrate, more serrate on one edge than on 
the other, so the involucral leaves match as well as the correspond- 
ing fingers on our two Fig. 106. 
hands. In the green- 
house of the Michigan 
State Agricultural Col- 
lege, isa plant unknown 
to me, presented by Dr. 
Gray. Theleavesareon — tInyotucre of Carpinus Americana, Blue Beech, the upper 
petioles three-fourths Roe ee ee 
of an inch in length; they are probably three ranked (certainly 
not two ranked). As the leaves droop, the upper lobe is much 
fullest and the midrib considerably curved as in Begonia. 
So we have unequal lobed leaves on stems where they are two, 
` three or four ranked. The common sheep sorrel often has one 
lobe longer and larger at the base, but I am unable to find any 
rule with regard to this fact. 
The four o’clock of our gardens Mirabilis has opposite leaves, 
and when of proper size, terminates each axis with a flower. 
The axillary bud on each side develops into a branch terminating 
Fig. 105. 
