JULY, 1900. GRAENICHER— FERTILIZATION OF SYMPHORICARPOS, ETC. 151 
significance. Our humming-bird, Trochilus coliibris, L., an 
occasional visitor, may carry pollen on its beak and act as a cross- 
fertilizer. 
In LoniccvLi tatanca we have an adaptation to the smaller bees, 
such as Osmia, Megachile, Halictus, etc. ; this is indicated by the 
short tube, the short stamens and style and the erect position of 
the flower. 
Lonicera dioica, Smooth-Leaved Honeysuckle* 
(Fig:. 5.) 
A comiimon species, blooming from May 22 to June 7. The 
flowers are collected in whorls at the ends of the branches, a 
branch bearing, as a rule, two whorls of about 6 flowers each. 
They are usually of a dark purplish color, but occasionally plants 
are found in our neighborhood producing greenish-yellow flow- 
ers only. While in the bud, the flower is erect, but after opening 
it assumes a horizontal position. The corolla tube is 8 mm. long 
and 4 mm. wide at its mouth and becomes only slightly narrower 
towards its base. Immediately above the base is a distinct dila- 
tion of the tube, the seat of the nectary. Numerous hairs, grow- 
ing on the inner surface of the tube, afford protection to the 
deeply concealed nectar. The outer lobe of the corolla, represent- 
ing the lower lip, is directed downward, while the remaining lobes 
participate in the formation of an upper lip. The anthers are 
situated 9 mm. above the entrance to the corolla tube, but they 
are 3 mm. behind the stigma. In some flowers the anthers begin 
to shed their pollen within the bud, a very short time before the 
latter opens ; in other cases newly opened flowers may be observed 
with the anthers still closed. There certainly exists much irreg- 
ularity in this respect, while of the stigmas it may be stated, that 
they always emerge from the bud in a receptive condition. 
Accordingly we have either a case of homogamy or of short-lived 
protenogyny. Inside of the bud, which is about to open, the 
capitate and receptive stigma is firmly pressed against one of the 
corolla lobes ; in this way contact between the stigma and one of 
the prematurely opening anthers is prevented and for this reason 
spontaneous self-fertilization can hardly take place within the 
bud. 
In favorable weather the flowers of this species open at all 
hours throughout the day. Lonicera dioica is a bumble-bee 
flower. Bumble-bees are the visitors, which on account of the 
length of the stamens and style are the most capable of coming- 
in contact with the anthers and the stigma, while sucking honey. 
Cross-fertilization is favored by the stigma being in advance of 
