z 
330 THE FERTILISATION OF FLOWERS. [PART ILI, 
florets of the disk, the throat, into which the honey rises, is s 
1 mm. deep, so that the honey is accessible to the most shores 
lipped insects. In the first stage (Fig. 112, 6), the pollen, and in 
the second (Fig. 112, 7), the stigmas, stand immediately above the 
corolla; insects moving over the capitulum must cross-fertilise many 
florets simultaneously. The branches of the style end in a thick 
tuft of divergent hairs (/, 8), which sweep the pollen out of the 
anther-cylinder (p, 6) as the style elongates. The inner surface of 
each division of the style bears two broad rows (k’, 8) of sigue 
papille, separated by a narrow interval; these stigmatic papil ee 
extend over the outer edges, and are there regularly dusted hb 
pollen if the pollen Has has got heaped above the anthers 
cylinder by the protruding style is not removed by insects. Self- 
fertilisation is as inevitable in absence of insects as cross-fertilisation 
is when their visits occur. The stigmatic surfaces in the margir -. 
florets are just as in the florets of the disk ; but the now functionles 
sweeping-bairs are distinctly shorter in the marginal florets. 
Visitors: A. Hymenoptera—(a) Apide: (1) Prosopis communis, N. $i 
(2) Sphecodes gibbus, L. @ ¢, all varieties, including ephippia, L.; (8) H 
lictus maculatus, Sm. 2 g,¢.p. and s., freq. ; (4) H. leucozonius, Schr. 2, Pe : 
(5) H. albipes, F. ¢,s.; (6) H. eylindetan F. 2 g,¢.p. and s., very ab. ; A 
H. villosulus, K. 2 g, cp. ands.; (8) H. rubicundus, Chr. 9, e.p. ; (9) An 
drena xanthura, K. 9, s.; (10) A. nigrownea, K. 2, ep.; (11) Colletes 
Davieseana, K. 2 ¢,¢.p. and s., very ab. ; (12) Bombus terrestris, L. 9, 8.5 
once. (Here also Delpino’s distinction between Composite adapted for Ha- 
lictus and those adapted for bees with abdominal brushes falls to the ground, 
for though the flat disk of Chrysanthemum leucanthemum must, according to 
Delpino, be fertilised mainly or exclusively by bees with abdominal ite 
found no such bees on it, but many specimens of Halictus, Andrena, 2 
Colletes). (b) Sphegide : (13) Cerceris variabilis, Schrk. ; (14) Crabro cepha: 
lotes, Shuck. 9; (15) Cr. cribrarius, L., oe 6, freq.; (16) Oxybelus 
uniglumis, L., Dlb., ab.; (17) O. tridpinosam F .3 (ce) Ichneumonide : (18) 
Various sp. ; (d) Tenthr edinide : (19) Tenthredo (Allantus) notha, K1., s. ; (20) 
T. scrophularie, L. ; (21) Several undetermined sp. of Tenthredo ; (22) Cim 
bex sericea, L. B. Diptera—(a) Empide: (23) Empis rustica, ee (b) Stra- 
tiomyide : (24) Nemotelus pantherinus, L., exceedingly abundant, sucking ; 
(25) Odontomyia viridula, F., very ab., s.; (c) Bombylide: (26) Systechus 
sulfureus, Mikan, s. (Sld.) ; (d) Sirpbhdle (27) Pipiza lugubris, F. ; be 
Cheilosia fraterna, Mgn.; (29) Syrphus nitidicollis, Mgn., fp. ; (30) Meli 
threptus teeniatus, Mgn., f.p.; (31) Volucella pellucens, L. (Sld.) ; ‘(32) Syritta — 
pipiens, L., s. ; (33) Eristalis Bp neta . 3 (84) E. horticola, Deg. (Sld.) 
(35) E. semdobum, 2 .; (86) E. sepuleralis, L. ; (87) E. eeneus, Scop., all five 
species very ab., f.p. ; (88) Helophilus floreus, L., fp. ; (89) H. pendulus, Le 
(e) Conopide : (40) Conops flavipes, L., s. ; (41) Sicus ferrugineus, L., 8.3; (F7 ) 
Muscidae : (42) Echinomyia tesselata, FE. ; (48) Pollenia Vespillo, F., fp. a 
8. 5 (44) Lucilia cornicina; F: ; (45)-L. silvarum, Mgn. ; (46) Pyrellia eT 
