ora 
yarrun] THE MECHANISMS OF FLOWERS. 93 
(b) Vespide : (22) Vespa holsatica, F. 9; (23) V. rufa, L. §. C. Coleop- 
tera—(a) Dermestide: (24) Attagenus pellio, L.; (b) Coccinellide: (25) 
Coccinella 14punctata, L. All were sucking honey ; Bombus pratorum and 
Andrena fulva were also collecting pollen, See also 590, 1., and 609. 
Orv, NYMPH MACE &, 
19. NupHAR LUTEUM, Smith.—The sepals, as Sprengel clearly 
showed, have, by their increased size and the yellow colour of their 
upper surface, taken on the function of a corolla: the under side 
of the petals secretes honey. Sprengel found only small beetles of 
the genus Meligethes in the flowers: I have seen besides Meligethes 
' various flies and other small beetles creeping about the flowers and 
flying from one to another; they effected self-fertilisation and 
_ cross-fertilisation indifferently. I was only able to catch Onesia 
 floralis, R.D. (Muscidae), and Donacia dentata, Hoppe (Chryso- 
_ melide); both were richly dusted with pollen. 
Nymphea alba, L., and Victoria regia, Lind., are, in Delpino’s 
opinion, fertilised by Cetoniw and Glaphyride. See also No. 775. 
Orv, PAPAVERACE ZL, 
20. PAPAVER Rua@as, L.—The numerous anthers stand close 
round the stigma, and dehisce before the opening of the flower. 
They cover themselves with pollen, part of which reaches the 
_ lower part of the stigmatic lobes, while the higher central parts 
of the stigmatic lobes protrude free from pollen. Its flowers 
' contain no honey, and are therefore visited solely by pollen-seeking 
insects, which find the broad stigmatic surface the most convenient 
| place on which to alight. They necessarily accomplish cross- 
_ fertilisation if they have come from another flower, and this 
cross-fertilisation probably prevails in its action over the self- 
| fertilisation which has already taken place. 
Visitors: A. Hymenoptera—Apide: (1) Halictus sexnotatus, K. 2, very 
' ab, ; (2) H. flavipes, F. 9, ab; (3) H. longulus, Smith, 9; (4) H. cylindri- 
_ cus, K. 9; (5) H. maculatus, Sm. 2; (6) Andrena dorsata, K. 2, ab. ; (7) A. 
_ tulvicrus, K. ? ; all collecting pollen, and dusted thickly with it. B. Diptera 
| —Syrphide ; (8) Cheilosia, fp. C. Coleoptera—Nitidulide : (9) Meligethes, 
very ab., fp. D. Orthoptera—(10) Forficula auricularia, L., both larvee and 
perfect insects hiding in the base of the flower, See also No. 590, I. 
Whether, in default of insect-visits, the self-fertilisation which 
inevitably takes place leads to development has still to be decided 
by experiment, Probably it does so, as Hildebrand has found that 
