- PART III. | THE MECHANISMS OF FLOWERS. 179 
94. MepIcAGo FALCATA, L.—Though on the whole the flower 
of this species resembles that of JM. sativa, it possesses certain 
peculiarities which facilitate explosion, and make it more difficult 
_ for bees to obtain the honey without releasing the column. For the 
_ pouches directed forwards and the processes directed backwards on 
the alz grasp the column less firmly, as may be seen in 2, Fig. 57, 
so that a less pressure is followed by explosion; but on the other 
hand a thin proboscis can pass more easily to the base of the flower 
without bringing about explosion. The ale leave less room for a 
proboscis to enter, as they are shorter and broader and rest on the 
Fic. 57.—Medicago faicata, L. 
; P —Flower, viewed obliquely from above. 
— Ditto, after removal of calyx and vexillum, from above. 
- 3 — Left ala, 4.— Carina. 
a 5.—Exploded flower, after removal of vexillum, seen obliquely from ‘the right and above; the 
olumn appears considerably foreshortened 
a, calyx ; b, vexillum; ¢, pathfinder ; d, claw of ala; e, lamina of ala ; f, invaginated process of 
ale directed forwards ; : 9, lobe of ala directed backwards ; h, coherent claws of earina; i, coherent 
lamine of ditto; kk, carinal pouches, which receive "Ne processes f; 1, column; m, superior free 
 Stamen; nn, entrances to the oney ; 0, stigma. (xX 7 
en tn 
, a ai S 
by ——f a 
carina for a shorter space in their basal half. Accordingly, of the 
gery many bees which I observed on flowers of M. falcata, I did not 
ee one sucking or collecting pollen on unexploded flowers without 
releasing the column, but I saw many Lepidoptera sucking without 
causing explosion. The flowers of J. sativa seem fitted rather for 
Seabsation by Lepidoptera, and those of MW. falcata rather for ferti- 
sation by bees. And my lists may lead us to conclude that the 
flowers of M. sativa offer special attractions for Lepidoptera, and 
N 2 
