380 THE FERTILISATION OF FLOWERS. [parr im. 
the stigma, even when the flower first opens, is capable of causing 
pollen-grains to adhere to it, and is not rarely found dusted with | 
pollen at that period. Thus cross-fertilisation is insured rather — 
by the position of the stigma in advance of the anthers than, 
as Severin Axell supposes, by proterandrous dichogamy. Self- 
fertilisation does not occur. 4 
A. Hymenoptera—(a) Apide: (1) Apis mellifica, L. §, very ab., sucking - 
only ; (2) Bombus terrestris, L. 2 § ¢,s. (as late as Oct. 14) ; (3) Diphysis — 
serratule, Pz. 2, s.; (4) Saropoda bimaculata, Pz. 9, s., with pollen of 
Calluna among its collecting-hairs ; (5) Andrena fulvicrus, K. 9,s.; (6) A. 
fuscipes, K. 9 ¢, s.; (7) A. dorsata, K. 9; (8) A. parvula, K. 9; (9) As 
simillima, Sm. ? ¢, the last three s. and c.p.; (b) Vespide: (10) Vespa 
holsatica, F. $,s. B. Diptera—Syrphidew : (11) Chrysotoxum octomaculatum, 
Curt. ; (12) Melithreptus scriptus, L. ; (13) Syritta pipiens, L.; (14) Seri- — 
comyia borealis, Fallen (Thuringia) ; (15) Cheilosia scutellata, Fallen; (16) 
Syrphus sp., all sucking. C. Thysanoptera—(17) Numerous species of Thrips. 
See also No. 590, III. ‘ 
Treviranus’ general assertion (742) that Ericacez fertilise them- 
selves before the flower opens needs no further contradiction after 
the foregoing examples. 
Tribe Rhodorew. 
Loiseleuria (Azalea) procumbens, L.—While the higher passes of — 
the Alps are still covered with snow under the hot June sun, the — 
projecting hillocks are carpeted with the red or crimson flowers of 
Loiseleuria. Numerous flies, humble-bees, and Lepidoptera fly 
from one tuft to another over the snow in search of honey, and as the 
flowers are proterogynous, cross-fertilisation takes place regularly — 
(609). | | 
Kalmia.—The striking peculiarity of this genus,—viz. that — 
the anthers are held fast in pouches of the corolla, until an insect- 
visitor touches the elastic, outwardly-bent filaments, setting them 
free and letting them return to their erect position,—was described 
in the case of K. latifolia, L., (K. polifolia, Wngnham.) by Sprengel, 
but was explained by him as a contrivance for self-fertilisation. — 
Dr. Hasskarl seems even to suppose that this beautiful mechanism — 
simply serves for spontaneous self-fertilisation ; for he says nothing 
about the action of insects, and declares that the stamens release — 
themselves spontaneously and effect self-fertilisation (313). 
ss In Die Alpenblumen the figure of this flower has been accidentally assigned to 
Empetrum nigrum (fig. 67). 
a 
ae 
