486 THE FERTILISATION OF FLOWERS. [PART III. 
(54—6), sucking the female flowers in the normal way ; (18) Andrena fulvi- 
crus, K. ? (33), cp.; (19) A. fulva, K. 9 (3), trying in vain to reach the 
honey ; (20) A. albicans, K. ¢, do. ; (21) Halictus lucidulus, Schenck. 9, do. 
B. Diptera—(a) Bombylide: (22) Bombylius discolor, Mgn. (12); (23) B. 
major, L. (10), ab. ; both species suck, but only occasionally effect fertilisation ; 
(6) Syrphide : (24) Rhingia rostrata, L. (LI—12), s.; (25) Eristalis intricarius, 
L., fp. C. Lepidoptera—(a) Rhopalocera : (26) Pieris brassice, L. (15) ; (6) 
Sphinges : (27) Macroglossa fuciformis, L. (Stromberg) ; (28) M. stellatarum, 
L.; all three species suck, but rarely effect fertilisation. . 
350. SCUTELLARIA GALERICULATA, L.—I have seen no insects 
visit this flower except a butterfly, Rhodocera rhamni, L. 
351. MELITTIS MELISSOPHYLLUM, L., is visited by Bombus 
hortorum, L. 
352. STACHYS SILVATICA, L.—The tube is 10 to 11 mm. long. 
The very thick, fleshy base of the ovary secretes honey, which 
fills 2 to 3 mm. of the tube, and is sheltered from rain by a ring of © 
stiff hairs which stand almost perpendicular to the wall of the 
corolla. The vaulted upper lip is rather small, but, owing to the 
almost horizontal position of the flower, it completely covers the 
anthers and stigmas; the under lip is very large and trilobed, and 
serves as a platform for the bees. The flowers, as Sprengel per- 
ceived, are distinctly proterandrous; in the young flower the — 
anthers are found to have dehisced on their inferior aspect while 
the end of the style lies behind them, with its stigmatic branches — 
very slightly divergent; in old flowers the end of the style is 
curved down below the anthers and its stigmatic divisions are — 
widely separated. If insect-visits occur, the fertilisation of old 
flowers with pollen from young is thus rendered inevitable; in 
absence of insects, self-fertilisation is frequent, as may be easily 
demonstrated on plants kept in the house, for the stigmas gradually 
bend down between, and come in contact with, the anthers, whose 
lower surfaces are still covered with pollen. The visitors for which 
the flower is especially suited are bees with a proboscis not less 
than 8 mm. long; and the tube is long enough to secure the 
honey against most flies. : 
g 
Visitors : A. Hymenoptera-—Apide : (1) Anthidium manicatum, L. ? Se 
(9—10), as abundant as on Ballota nigra ; (2) Anthophora quadrimacula ¥ 
Pz. 2 g (9—10), do. (Thur., Sld.) ; (3) A. furcata, Pz. 9? ¢ (11—12), less freq. 
(Thur.) ; (4) Bombus agrorum, F. $ 9 (10—15), ab.; (5) B. pratorum, L. 
% d (8-10) ; (6) B. hortorum, L. ¢ (17—18), all sucking normally. B. 
Diptera—Syrphide : (7) Rhingia rostrata, L. (11—12), s. ; (8) Xylota silyarum 
L. (Warstein), trying vainly to reach the honey. 
