THE AMERICAN BOTANIST. 
103 
in it. * The flowers are overrun with ants and small 
beetles that should prove most effective agents in pollina- 
tion if the pistils could be affected by the pollen in the 
same flower. The plant, however, rarely produces much 
fruit in the northern parts of its range, though the flowers 
are usually abundant and each contains several pistils. 
The larvae of an interesting butterfly, the zebra swallow- 
tail (IphicHdes ajax) feeds upon the papaw and it is sug- 
gested that the adult insect is the species likeliest to affect 
cross-pollination. This insect, like the tree itself, is rather 
southern in its distribution, and its rarity may account 
for the scarcity of fruits in the Northern States. It may 
be queried in passing how the ants discover so quickly 
that the papaws are in bloom. In flowers nearer the 
ground their presence is not so surprising, but in papaw 
flowers twenty feet or more in the air one might expect to 
find them absent. 
Late in Autumn the banana-like fruit ripens. At 
maturity it is four inches or more long, a third as broad, 
and reddish yellow with a thick rind that encloses a soft 
fragrant pulp in which are embedded a half a dozen or 
more large smooth seeds. The pulp is edible and has a 
flavor that at once brings to mind the flavor of the tropi- 
cal fruits of this family if one has ever eaten them. Tp 
many palates the flavor is too strong to be agreeable, but 
there is enough demand for the fruit in some sections to 
to cause it to be sent to market in some quantity. The 
leaves remain on the tree until late in the Autumn and be- 
fore falling turn to a rich clear yellow that lights up the 
thickets for some days. 
ABOUT MILKWEEDS. 
BY DR. WILLIAM WHITMAN BAILEY. 
OTHING can be more singular than the structure of 
milkweed flowers. If one compares them with the 
morphologic ideal of a flower, or with one which actually 
approaches the unit, we fail utterly to refer some of the 
parts. They are aberrant and almost bizarre. 
