BO4 THE FERTILISATION OF FLOWERS. [PART 11] 
taneously with the stigma, and project from the tube ; the anther 
dehisce laterally, but so widely, that the whole of their inne 
faces are covered with pollen. The two anthers stand sometime 
wide apart (Fig. 130, 4), at other times they bend inwards ove 
the stigma (1, 2); in the former case, an insect’s proboscis ir 
entering the flower first touches with one side an anther, anc 
immediately afterwards the stigma with the opposite side, and s¢ 
passing from flower. to flower. leads to. eross-fertilisation ;-in -the 
latter case self-fertilisation and. cross-fertilisation may result- ir 
differently. Insect-visits are very scarce by day; perhaps tl 
/ LA mt 
a = fins 
CY, 
Sa 
Fic. 130.—Ligustrum vulgare, Li. 
1.—Flower, seen obliquely from above. 
2. —Ditto, not so far advanced, seen directly from above. 
3, 4.—Flowers, seen from the side, after removal of half the corolla (x 33). 
white, sweet-scented flowers attract nocturnal Lepidoptera ‘in 
greater numbers. Flowers whose anthers are inclined inwards 
above the stigma always fertilise themselves in absence of insects 
7 
A. Hymenoptera—Apide : (1) Heriades truncorum, L., s. (June 27, 1869). 
B, Diptera—Syrphide : (2) Eristalis nemorum, L., s. (June 21, 1868). A furthe: 
list of visitors (four beetles, two flies, two bees, seven Lepidoptera) is given in 
No. 590, 111. SA VE 
Orv, APOCYNACEZ. 
293. Vinca minor, L.—The structure of the flower was 
correctly described by Sprengel, but incorrectly explained, since 
he overlooked here, as elsewhere, the advantage of cross-fertilisa- 
tion, Sprengel had. found Thrips, but no other insect, in the — 
flower, and he supposed that in creeping in and out of the flower — 
it transferred pollen to the stigma of the same flower, and-that in — 
this way alone fertilisation was effected, ie’ a 
Darwin (153) gave the first correct account of the mechan- 
ism of Vinca, for he recognised that a long thin proboscis in 
passing into the flower gets smeared with adhesive matter, and t 
> oh 
5 
- 
- 
