BULLETIN 
TORREY BOTANICAL CLUB. 
Vol. XX. New York City and Lancaster, Pa., Jauuary 15, 1893. No. 1 
Studies upon Akenes and eae of Plants of the Order Composite. 
By W. W. ROWLEE. 
(PLatEs CXXXIV.—CXXXVIIL.) 
General Observations. 
The fruit of the plants, belonging to the Order Compositz is 
no less remarkabie for its variety of external form than for its 
uniformity in internal structure. In the mature fruit, the calyx 
and the carpellary coats are completely combined, so that they 
cannot be distinguished by any structural differences. The integ- : 
ument of the seed may be separated from the others, and is a deli- 
cate polished membrane, wrapped rather closely around the em- 
bryo. The limb of the calyx, although sometimes obsolete (Chry- a 
santhemum Leucanthemum et. al.) more often appears as a crown 
or cup (Anthemis arvensis et. al.) or a set of teeth or scales (Helen-— 
ium autumnale et. al. ) or as a tuft of bristles or hairs (Aséer et. al.) 
When the limb of the calyx takes on any of these forms it is called 
the pappus. In Lactuca, Taraxacum, et. al., the pappus is raised 
far above the akene by a prolongation of the calyx into a slender 
beak. The akene may be terete, striate, ribbed, angled, or 
winged. It may be glabrous, hairy, silky, or even spiny. It is 
usually larger above and tapering downward, but this is not always 
the case. There is more or less of an opening left at the base of 
the akene when it falls from the receptacle through which the 
hypocotyl emerges when the seed germinates. These are but — Ss 
a few of the general ways in which the akene varies externally. 
- To enumerate all the variations would necessitate a description 
of every species. 
