JULY, 1900. GRAENICHER— FERTILIZATION OF SYMPHORICARPOS, ETC. 147 
S. symphoricarpos (5) 
S. racemosus (6) 
S. racemosus (7) 
S. racemosus [8) 
S. racemosus 
S. occidentaiis 
Southern Illinois. 
Germariy 
Germany 
Belgium 
Milwaukee, Wis. 
Milwaukee, Wis. 
T3 C 
</) fc 
2 
1 
28 
19 
1 
13 
14 
29 
15 
Lonicera, L« Honeysuckle* 
Lonicera furnishes an example of a genus, producing numer- 
ous species, which present a great amount of variation in their 
floral characters, and, for this reason are adapted to various kinds 
of visitors. The main factor which separates the species from 
each other is the variation in length and width of the corolla tube, 
while points of minor importance, such as difference in length 
of stamens and style, in color, in position of the flower (erect 
or pendulous) etc., have also a determining effect. The length 
of the corolla tube in the different species corresponds more or 
less with the length of the tongues of their visitors and accord- 
ingly we come across wasp-flowers, bee-flowers, bumble-bee - 
flowers, hawk-moth-flowers and bird-flowers among the honey- 
suckles. 
Lonicera alpigena, L., a. native of the Alps has a short wide- 
mouthed tube and is visited mainly by wasps. This is the only 
wasp-flower among the species of Lonicera. Other short-tubed 
species are adapted to the smaller bees, while in the bumblebee-' 
flowers the tube ranges from 4 mm. to about 20 mm. in length. 
Two European honeysuckles, L. periclymenuin, L. and L. capri- 
foliiim, L. are fertilized by hawk-moths in the evening and have 
long, narrow tubes of 22 to 30 mm. in length. The trumpet- 
honeysuckle, L. sempervircns, Ait. with its bright scarlet flowers 
is a native of this country, but occurs in our latitude in a culti- 
vated state only. The slender flowers attain a length of 25 to 
35 mm. and are adapted to the ruby-throated humming-bird, 
Trochiliis coluhris, L. 
(5) C. Robertson, loc cit., p. 174. (7) H. Mueller, loc. cit., p, 361 and Weitere Beobacht- 
ungen. Vol. Ill, p. 73, (7) E, Loew. Weitere Beobachtungen ueber d. Blumenbesuch von 
Insekten, etc., Jahresb. d. Bot. Gart. Berlin, Vol. IV. p. 99. (8) MacLoed, loc. cit., p. 119. 
