256 PRACTICAL COURSE IN BOTANY 
and hollowed out with the calyx sepals at the top. Cut a 
cross section midway between the stem and the blossom end, 
and make an enlarged sketch of it. Label the thin, papery 
‘walls that inclose the seed, carpels. 
How many of them are there, and how 
many seeds does each contain? The 
carpels, together with all that portion 
of the fruit which surrounds and ad- 
heres to the ovary, constitute the peri- 
carp, or wall of the seed vessel. The 
fleshy part of the apple is no part of 
the ovary proper, but consists merely 
Fig. 368.— Cross section 
of a pome: pil, placenta; c, Of the receptacle, or end of the foot- 
earpels ; f, fbrovascular bun- stalk, which becomes greatly enlarged 
ta and thickened in fruit. Look for a 
ring of dots outside the carpels, connected (usually) by a 
faint scalloped line. How many of these dots are there? How 
do they compare in number with the carpels? With the rem- 
nants of the sepals adhering to the blossom end of the fruit? 
Next make a vertical section 
through a fruit, and sketch, enlarg- 
ing it sufficiently to show all the 
parts distinctly. Observe the line of | 
woody fibers outside the carpels, in- 
closing the core of the apple. Com- 
pare this with your cross section; to 
what does it correspond? Where do 
these threads originate? Where do 
they end? Can you make out what Fic. 369.— Vertical section 
Me aust (FO), Noties Row aul ate peer ae 
where the stem is attached to the ji, placenta: c, carpel. ” ; 
fruit. Label the external portion of 
the stem, peduncle; the upper part, from which the fibrovas- 
cular bundles branch, the receptacle. It is the enlargement 
of this which forms the fleshy part of the fruit. Try to find 
out, with the aid of your lens and dissecting pins, the exact 
