500 , THE FERTILISATION OF FLOWERS. [PART III. 
pollen on the bee’s head. Gradually the filaments bend backwards 
(2, 1, Fig. 169) out of the bee’s way, while the two stigmas spread 
more and more apart, bending slightly forwards into the place 
where the anthers were before. In absence of insects, self-fertili- 
sation rarely takes place, for the stamens as a rule do not touch 
the stigmas; yet in a good many flowers the anthers come in 
contact with the stigmas in oncom. backwards, and dust them 
with pollen. 
Honey is secreted by the tissue below the ovary, as in all the 
Labiates that I have examined (cf. Fig. 168, 3), and so plentifully 
that the corolla-tube (which is 9 to 10 mm. long) is often filled 
to a depth of 4mm. The flowers are rendered conspicuous by 
Fic. 169.—Teucriwm Scorodonia, L. 
1.—Flower, in first (male) stage (x 33). 
2.—Ditto, at the beginning of the second (female) stage. 
3.—Ditto, at the end of the second stage. 
aggregation, and in spite of their dull colour they are so abundantly 
visited by insects as to. be able to dispense with the power of self- _ 
fertilisation. 
Visitors : A. Hymenoptera—Apide: (1) Bombus pratorum, L. § 9 (8— 
114), s., very ab. ; (2) B. agrorum, F. $ 9 (10—15), do. ; (3) B. hypnorum, 
L. ¢ (10), s.; (4) Anthophora quadrimaculata, Pz. 9 (9—10), s.; (5) Saro- 
poda bimaculata, Pz. 9 ¢ (9), very ab., s. B. Diptera—Syrphide : (6) Eri- 
stalis nemorum, L., f.p., and thus only able to effect fertilisation occasionally. — 
It is noteworthy that the honey-bee (whose proboscis is 6 mm. long), was not 
observed on this abundantly nectariferous flower. It would be just able to 
taste the honey. See also No, 590, 111. 
According to Dr. Buchanan White, Zeucriwm Scorodonia is 
visited by many nocturnal Lepidoptera (773). 
