122 Trans. Acad. Sci. of St. Louis. 
33, the movement is also of advantage in windy weather, 
since bees as a rule move against the wind and always turr 
with their heads towards it when alighting, so that the move- 
ment of the flowers turns them in such a position that the bees 
are most likely to be attracted by their odor and color, and 
can readily land upon them. 
The flowers are rose or fiesh-color, measure about 25 mm. 
long and, when collected in the spikes, make a splendid dis- 
play. The Labiate form is somewhat modified by the enlarge- 
ment of the mouth of the tube, which admits the head and 
thorax of a bumble-bee. The anthers and stigma are protected 
under the upper wall, and the pollen is dusted upon the upper 
part of the bee’s thorax. The proterandry of the flower was 
first recorded by Delpino.* 
The narrow part of the tube is about 9 mm. long. The 
flower is visited abundantly and almost exclusively by Bombus 
americanorum F. 298. Ihave also seen it visited by single 
individuals of Melissodes bimaculata Lep. 3, Meguchile brevis 
Say ¢, Danais archippus F. and Colias philodice Godt. At 
Mt. Carmel, in Southern Illinois, according to Schneck, Bot. 
Gaz. XVI., 312, the flower is perforated by Xylocopa virgin- 
ica. This bee is rare in my neighborhood ; I have never seen 
but two individuals. 
Marrubium vulgare | L.— ‘* Nat. from Eu.’’ — The corolla 
is white, the upper lip narrow and cleft, the lower three- 
lobed. The stamens are included in the corolla tube, so that 
they are out of reach of pollen-insects, and the pollen is 
applied to the insect’s proboscis. The tube is about 5 mm. 
long. 
In Germany, Miiller found the flowers visited by 4 bees, 1 
Chrysid, 1 Empis, 1 bug, 1 beetle. Inthe Pyrenees, MacLeod 
saw it visited by Bombus terrestris. ‘The flowers bloom from 
May 28 to Oct. 5. June 22, 29, and Sept. 9, I observed the 
following visitors : — 
Hymenoptera — Apide: (1) Apis mellifica L. 8, ab.; (2) Bombus ameri- - 
* Ulteriori 
! osservazioni. 
+ See Miiller: Weit. Beobachtungen. 
