1898 | COMPARATIVE MORPHOLOGY OF PISTILS 299 
pistil, they curve in over the top of the axillary placenta, form- 
ing a forked suture shaped like an inverted letter Y. 
While the carpel has thus been curving upward, the growing 
nucellus has been bending downward, the former describing an 
arc of 180°, while the latter passes through only 120°. A short 
time before this stage is reached the archesporial cell is differen- 
tiated, the exact time being very variable. The wall of the 
pistil furthest from the receptacle now elongates considerably, 
with the result that the longest axis of the pistil instead of being, 
as at first, at right angles to the surface of the receptacle, is now 
parallel to it. The ovule still continues to bend until it, too, lies 
in the main axis of the pistil, but with the micropyle pointing 
down. The last small opening of the pistil is now closed by the 
meeting of the edges of the laminae. It is the line of meeting 
of the laminae with the upper side of the axillary placenta, or in 
other words, one of the arms of the inverted Y-shaped suture, 
that shows so distinctly in all median or almost median sections 
of the pistil (jig. 8, a). 
The main fibrovascular bundle supplying the pistil divides 
just after entering it. One branch passes around in the median 
line in a position corresponding to the bundle of the mid-rib of 
a leaf. The other passes up into the axillary placenta, through 
the funiculus and into the base of the nucellus, also in ‘the 
median line ( fig. 8). Later other branches run to the side walls 
of the pistil. 
RANUNCULUS EREMOGENES. The development of the pistil in 
this species is almost identical with that in &. abortivus. -The 
pistil begins as a rounded outgrowth from the receptacle (fig. 
9,2), which is more developed in this species at this stage, than 
in the preceding. Immediately above the base of this outgrowth 
there arises another, eventually to become the ovule. This is 
shown in fig. 9, at 6, which is a rudimentary pistil, with the 
still more rudimentary ovule three or four cells higher. The 
pistil flattens dorsiventrally and the edges begin to fold together, 
while the apex also curves upward. The axillary papilla at the 
same time elongates and the distinction of ovule and placenta 1s 
