70 THE FERTILISATION OF FLOWERS. [PART III. 
(b) Sphegide: (8) Oxybelus uniglumis, L., fp. ab. ; (9) Gorytes mystaceus, L., 
hovering over the flowers, perhaps in order to piunder flies ; (¢) Vespide: 
(10) Odynerus parietum, L. 9, do. B, Diptera—(a) Syrphidw: (11) Syrphus 
pyrastri, L.; (12) Helophilus floreus, L.; (13) Eristalis sepulcralis, L. ; 
(14) E. arbustorum, L.; (15) Syritta pipiens, L.; (16) Xylota ignava, Pz. ; 
(17) X. lenta, Mgn., all f.p.; (b) Muscide: (18) Prosena siberita, F. 
C. Coleoptera—(19) Trichius fasciatus, L., devouring the whole of the anthers. 
In Clematis Balearica, Rich. (C. cirrhosa, L.), the outermost 
stamens are metamorphosed into spoon-shaped nectaries, which are 
sucked by Bombus and Xylocopa ; in Clematis integrifolia, L., the - 
inner stamens secrete honey (567, p. 8). 
2. THALICTRUM AQUILEGIFOLIUM, L.—The stamens in this 
plant play the part of petals: they are of a pale lilac colour, 
thickened and club-shaped, and radiate outwards, forming consider- 
able bundles, fifteen to twenty mm. in diameter. When the 
flower opens, the stigmas are covered over and shielded from 
insects by the central stamens, which are crowded together and 
have their anthers still closed. In young flowers the insects 
alight upon the anther-bearing points of the stiff filaments, and 
climb with some difficulty around and over them in search of 
pollen. In older flowers the central stamens are directed more 
outwards, so that now the insects can alight more conveniently 
. upon the stigmas. Thus cross-fertilisation is accomplished. In 
default of insect-visits, self-fertilisation is provided for by part of 
the stigmas always standing in the way of falling pollen. 
_ The flowers are devoid of honey, and are Gilead oe by pollen- 
seeking insects, — 
A. Hymenoptera—-A pide : (1) Prosopis signata, Pz. ¢ 9, fp. ; (2) Halictus 
sexnotatus, K.?, c.p.; (3) Apis mellifica, L. $,¢p. B. Diptera—Syrphide : 
(4) Rhingia rostrata, L.; (5) Eristalisarbustorum, L. ; (6) E. nemorum, L. ; 
(7) E. sepulcralis, L. ; (8) E. tenax, L., all f.p. C. Coleoptera—(9) Trichius 
asciatus, L., devouring the anthers bodily. See also No. 609, p. 125. 
Atragene alpina, L.—The pendulous violet flowers only give up 
their honey to insects which can force asunder the numerous 
stamens, which are set closely in several whorls,—viz. bees and 
humble-bees; and in point of fact only these insects have been 
observed to fertilise the plant (590, 609). The grooved inner surface 
of the basal half of the filament secretes and lodges honey. 
3. THALICTRUM FLAVUM, L.—This plant, which is abundant . 
on meadows by the Lippe, has likewise honeyless flowers. I found 
