274 The Botanical Gazette. (May, 
nearly heart-shaped with long claws. At the base of the blade 
of each sepal there is a shallow depression containing two 
yellow nectar glands. The nectar is thus completely exposed. 
The claw of each sepal bears a stamen with an extrorse anther 
held in such a position as to touch a large insect which sips 
the nectar. The three outer anthers dehisce first. The per- 
fect flowers are proterandrous, the stigmas not becoming re- 
ceptive until the anthers have fallen. The three styles are 
strongly divergent, so that the stigmas may touch the insects 
visiting the sepals for nectar. 
€ flowers show a very peculiar assemblage of visitors, 
mostly flies and beetles. The latter seem to be the ones for 
which the adaptations are intended. Of these Trichius piger 
is the most abundant visitor that I have observed, and it can 
readily affect pollination. The flowers are of rather large 
size, and, owing to their completely exposed nectar, admit 
insects which can obtain nectar but can hardly touch anthers 
or stigmas. 
Melanthium Virginicum blooms from the 16th of June to 
the 11th of July. The list of visitors was observed on July 
3d and sth. 
sograpta marginata Say; RO i 
is 
piens L.; Tachi ogaster 0c 
a WIk.; (5 
wns.; Muscide: (11) Lucilia sp.; (12) L. cornicina F.; (13) Mus Eh 
ae L.; Anthomyide: (14) Anthomyia sp.; (15) A. albicincta *™ 
17) Trichius piger F’. freq.; Chrysomelida: (18) Diabrotica atripenns 
g Mordellide: (19) Mordella melaena /Sosiee 20) M. margin 
Melsh.; Curculionidae - (21) Centrinites strigicollis Casey—all S cide: 
XMENOPTERA—Andvenida : (22) Halictus confusus Sm. 2; 5p” aris 
¢3) ys ichneumonea L.; Chalcidide: (24) Perilampus triangul 
—all s. 
Carlinville, Illinois. 
