partrun] § THE MECHANISMS OF FLOWERS. 355 
_ covered all over their inner surface with stigmatic papille, spread 
apart, and gradually bend so far backwards that part of their 
_ stigmatic surface comes in contact with the hairs (Fig. 116, 2). Soif 
the pollen has not been removed by insects, self-fertilisation takes 
i pplace. If insect-visitors come in proper time self-fertilisation is 
not impossible, but the chances are immensely in favour of cross- 
F fertilisation, and of cross- -fertilisation with pollen from other capitula, 
as the insect on alighting comes at once in contact with the upper 
surface of the stigmas. 
~ 
Visitors: A. Hymenoptera—(a) Apidw: (1) Apis mellifica, L. $, s. and 
¢@p., ab. ; (2) Bombus lapidarius, L. §, s.; (3) Dasypoda hirtipes, F. 9, s. 
and c.p. ; (4) Panurgus calearatus, Scop. 2 ¢,s. and c.p., very ab. ; (5) Halictus 
- leucozonius, Schr. 9? ¢,'s. and «p.; (6) H. villosulus, K. 9 g, s. and cp. ; 
; (7) Megachile argentata, F. yy 8. ; (8) M. Willughbiella, K. ¢,s. ; (9) Celioxys 
Seiden, Ill. 2, s.; (10) C. simplex, Nyl. 9,8. ; (6) Chryside: (11) Hedy- 
m lucidulum, Latr. ¢. B. Diptera—(a) Syrphide : (12) Eristalis tenax, L. 
(as late as Oct. 13); (13) E. arbustorum, L. ; (14) Syrphus balteatus, Deg., 
all three species f.p. and s., very ab. ; (6) Conopide: (15) Sicus ferrugineus, 
. L., ee Occemyia atra, F, eg es oe : (17) Pieris 
-napi, L., ab. ; (18) Satyrus Megera, L. ; (19) Vanessa urtice, L., not rare ; 
_ (20) Hesperia sp., alls. See also No. 590, II. 
~~ 
_ 267. HIgRACIUM PILOSELLA, L.—Forty-two to sixty-four florets 
unite to form a capitulum, and increase in size from its centre to its 
circumference. In each the tube is 3 to 6 mm. long, and the limb 4 
to 8mm. long. In sunny weather the capitulum expands to form 
_ayellow surface 20 mm. in diameter, but in dull weather it closes up. 
“4 n the bare slopes where the plant grows abundantly, its capitula are 
conspicuous enough to attract numerous insects in spite of the small 
size of the plant. 
But on the whole, insect-visits are less abundant, though not 
less various, than in the previous species, and accordingly, while 
the flowers are in other respects similar, self-fertilisation is better 
provided for by the greater involution of the stigmas (Fig. 116, 4). 
Visitors : A. Hymenoptera—(a) Apide : (1) Panurgus calcaratus, Scop. ? ¢, 
ep. and s., ab. ; (2) Andrena fulvescens, Sm. ?; (3) A. fulvago, Chr. ? ; (4) 
Halictus leucozonius, Schr. 9; (5) H. villosulus, K. 2; (6) H. nitidus, 
Schenck, 9, all c.p., the two Andrenez also s. ; (7) Ceratina ccerulea, Villa, ¢, 
8, scarce ; (8) Diphysis serratule, Pz. ¢,s., scarce ; (9) Nomada Fabriciana, L. 
-9,8.; (b) Tenthredinide : (10) Cephus, a small sp. B. Diptera—(a) Bombylide : 
(1) Rombylivs canescens, Mik. (Sld.), s.; (0) Syrphide: (12) Helophilus 
floreus, L., fp. C. Lepidoptera—(a) Rhopalocera: (13) Pieris brassice, L. ; 
(14) Acetia argiolus, L. ; (b) Noctuew: (15) Euclidia Mi, L., all s. D. Cole- 
eee) Cerambycide : (16) Leptura livida, L. ; (8) Chuunin aA 
“A A 2 
