130 THE FERTILISATION OF FLOWERS. [.111 PART 
those of Stellaria, Cerastium, and Gypsophila paniculata, where 
the honey is fully exposed, and Dianthus and Saponaria, where 
it is only accessible to Lepidoptera. The insect-visitors include 
bees, Lepidoptera, and some long-tongued flies. The nectaries, 
which lie at the base of the stamens, cohere into a fleshy 
ring surrounding the ovary. The calyx tube is 6 to 7 mm. long, 
and bears teeth 3 mm. long, which stand erect and support 
the claws of the petals. The honey is thus accessible to insects 
which have a proboscis 9 to 10 mm. long; or which, with a pro- 
boscis at least 6 mm. long, have strength enough to push apart 
the claws of the petals, above the level of the calyx-tube ; or, 
finally, to insects small enough to creep down the tube. . 
The flowers are distinctly proterandrous. First, the five outer 
anthers dehisce, while standing in the entrance of the flower and 
having their pollen-covered sides turned towards one another. The 
tube, though it permits a butterfly’s proboscis to pass easily down, 
is so much obstructed by the anthers that the proboscis cannot fail 
to be dusted with pollen. These stamens then elongate, and bend 
outwards to lie in the intervals between the petals, while the inner 
whorls take their place in the entrance of the flower. When these 
wither, the five styles grow up, and the stigmatic papille, which 
clothe the whole of their inner surfaces, attain their full develop- 
ment. The styles reach to the entrance of the flower, and their 
ends make 13 to 2 spiral turns, so that an insect cannot fail to 
touch some part of the stigmatic surfaces with its proboscis in 
thrusting it down into the flower. 
The flowers are chiefly visited for the sake ot their honey; I 
have only seen the hive-bee collecting pollen, and two species 
of Syrphidze feeding on it. 
Visitors : A. Hymenoptera—Apide : (L) Bombus Rajellus, Ill. 9 (12 to 13) ; — 
(2) B. lapidarius, L. 2 § (10 to 14) ; (3) B. agrorum, F. ? (12 to 15); (4) B. © 
terrestris, L. § (7 to 9) ; (5) Apis mellifica, L. $ (6), ab., s. ande.p. ; (6) Osmia — 
rufa, L. 2 (9) ; (7) Andrena nitida, K. 9 (3 to 4), they sought in vain for honey in 
several flowers. B, Lepidoptera—(a) Rhopalocera: (8) Pieris brassicae, L. 
(15); (9) P. rape, L., both ab. ; (10) Lycena Icarus, Rott. ; (b) Sphinges: 
(11) Macroglossa fuciformis, L.; (12) Ino statices, L.; (c) Noctuew: (138) 
Euclidia glyphica, L., very ab. C. Diptera—-Syrphide : (14) Rhingia rostrata, 
L. (11 to 12), s.; (15) Volucella plumata, L., fp. ; (16) Syrphus pyrastri, 
L., f.p. 
I have observed the stamens of Z. flos-cuculi dusted with — 
butterflies’ scales, and a Pieris rape which I caught upon the — 
flower had a number of its pollen-grains among the hairs and — 
scales on the forepart of its head. 
