PART 111. | THE MECHANISMS OF FLOWERS. 427 
widens out above, and is smooth within, except that a ring of close 
woolly hairs surrounds it at the base of the funnel-shaped, ex- 
panded portion ; on a level with this ring, five similar rings of bairs 
surround the five stamens, and effectually exclude rain. The 
corolla divides above into five violet lobes, which spread out to 
a diameter of 16 to 22 mm, The funnel-shaped mouth is light- 
coloured, and marked with dark-violet lines (pafhfinders) coursing 
towards the base of the flower. Stigma and anthers ripen to- 
gether, and stand at the same height. The style is sometimes 
bent upwards above the anthers, as in the figure, but as a rule it 
is in immediate contact with them. Insect-visits, therefore, may 
lead equally well to cross- and self-fertilisation ; and in absence of 
insects self-fertilisation in most cases takes place, 
Visitors: Hymenoptera—Apide; (1) Apis mellifica, L. $, s., ab.; (2) 
Bombus agrorum, F, 9, s.; (8) B. lapidarius, L. 9, s., both very frequent. 
See also No. 590, Ill. 
Atropa Belladonna, L., is likewise adapted for humble-bees. 
I have seen it visited by nine species of bees and by Thrips 
(590, IIL.), 
Mandragora vernalis, Bert., is proterogynous, according to 
Hildebrand (351). 
LIochroma tubulosum, Benth., is proterogynous with persistent 
stigmas, The deep-blue, pendulous flowers are tubular, widening 
out at the mouth, and are supposed by Delpino to be fertilised by 
humming-birds (177). 
Scopolia carniolica, Jacq. (S. atropoides, Schult), is protero- 
gynous (351). 
316. HyoscyAMUS NIGER, L.—Cross-fertilisation is insured, 
or at least favoured, by the prominent position of the stigma. 
Sprengel found the plant visited by humble-bees, and the dimen- 
sions of the flower seem well suited to these insects. I have seen 
only Halictus cylindricus, F. 2, collecting pollen on the flower. 
Browallia elata, L.—The corolla is hypocrateriform, and its 
mouth is blocked by the much expanded filaments of the two 
superior stamens, which are inserted in the throat of the corolla ; 
these leave only two very narrow openings through which a thin 
proboscis may pass. The proboscis entering in this way touches 
the anthers (the inferior pair of which is inclosed in the tube), and 
also the stigma which stands between the two pairs of anthers ; the 
stigma smears the entering proboscis with viscid matter in the 
