PART III. | THE MECHANISMS OF FLOWERS. 307 
| ~ come in contact with the anthers of neighbouring flowers are, on the 
_ other hand, not uncommon. 
ah Visitors : A. Hymenoptera—Apide: (1) Apis mellifica, L. 8, ab.; (2) 
F Bombus pratorum, L. $, s.; (3) a small Halictus, 9 ¢,s. B. Diptera—(a) 
' Tabanide: (4) Tabanus luridus, Pz. ; (b) Empide: (5) Empis livida, L. ; (6) 
_ E. rustica, F., both species very ab., s. ; (c) Syrphide: (7) Eristalis nemorum, 
_ L.; (8) E. arbustorum, L. ; (9) E. sepulcralis, L. ; (10) E. horticola, Mgn. 
_ (Sid.) ; all four species ab., fp. ; (11) Volucella bombylans, L. ; (12) Helo- 
_philus floreus, L. ; (13) H. pendulus, L. ; (14) Syritta pipiens, L. ; (15) Chry- 
sotoxum festivum, L., all sometimes s., sometimes f.p; (d) Conopide: (16) 
Sicus ferrugineus, L., s.; (e) Muscide: (17) Sarcophaga carnaria, L. ; (18) 
- Onesia floralis, E. D. ; (19) Lucilia cornicina, F. ; (20) Musca domestica, L. ; 
(21) Calliphora erythrocephala, Mgn. ; (22) C. vomitoria, L., all ab.,s. See 
also No. 590, 11. I have found it visited on the Alps by one beetle, sixteen 
species of Coleoptera, and fifteen Lepidoptera (609). 
209. VALERIANA DIoIcA, L.'—Honey is secreted as in the 
previous species, but cross-fertilisation is ensured not by dichogamy, 
but by dicecism. The male flowers, being notably larger than the 
_ female, are almost always visited first by the insect, .as I have 
repeatedly observed. Sprengel insisted rightly that in this order 
_ alone could the insect-visits be useful to the plant. _ In the male 
florets the tube is 2} to 34 mm. long, widening above; in the 
female it is only 1 mm. long, so that in both the honey is accessible 
to insects with very short proboscides. The capitulum is much 
less conspicuous than in J, officinalis, but the flowering period is 
so early that the plant is exposed to much less competition. Insect- 
visitors are less various than in the previous case, but still fairly 
numerous. In this plant there are four kinds of individuals, with 
four different kinds of flowers: (1) male flowers without any rudi- 
- ment of a pistil, and with large corollas; (2) male flowers with 
a rudimentary pistil, and a somewhat smaller corolla; (3) female 
flowers with evident traces of anthers, and with still smaller corollas ; 
(4) female flowers with scarcely visible traces of anthers, and with 
_the smallest corollas of all (No. 584, p. 131). 
Visitors : A. Hymenoptera—A pide : (1) Apis mellifica, L. $,s, very ab. ; 
 ) Andrena albicans, K. 9, freq. B. Diptera—(a) Syrphiden - (3) Eristalis 
| Seebustorum, L., s. ; (4) Rhingia rostrata, L., fp. ; (0) Tipulide : (5) Tipula, 
“sp.,s. CO. Papldspters—Rkopalocera ; (6) Pieris napi, L.,s. D. Coleoptera— 
| Nitidulide : (7) Meligethes, very ab. | 
? AR 
) Valeriana montana, L., is ; gynodicecious, some plants having 
distinctly proterandrous, hermaphrodite flowers with a large corolla, 
=. a> 1 Compare Sprengel, No. 702, pp. 65-67. 
2 x 2 
