PART III. | . THE MECHANISMS OF FLOWERS. 359 
Schenck, 2, c.p. and s. ; (4) Cilissa melanura, Nyl. ?; (5) Andrena denticu- 
lata, K. 2, s. and ep. (Sid. Thur.); (6) A. fulvicrus, K. 2, ¢.p.; (7) A. 
_fulvescens, Sm. 9, ¢.p. (Thur.) ; (8) A. fulvago, Chr. ?, cp. (Thur.); (9) 
_ Halictus villosulus, K. ¢, c.p.; (10) H. leucozonius, Schr. 2 ¢, ep. and-s., 
_ very ab. (Thiringer Wald, August 30, 1869) ; (11) H. cylindricus, F. 2 ¢, cp. 
- ands. ; (12) H. maculatus, Sm. ¢, s. ; (13) H.Smeathmanellus, K. 9, c.p. ; (14) 
Hz. flavipes, F. ¢, s.; (15) H. lugubris, K. ¢,s. B. Diptera—Syrphide : (16) 
 Eristalis arbustorum, L., s. and f.p. ; (17) E. tenax, L., do., both species ab. ; 
_ (18) Syrphus balteatus, Deg., do. C. Lepidoptera—Noctue: (19)  Plusia 
gamma, L., s. (as late as Oct. 14). See also No. 590, 111. 
274. TARAXACUM OFFICINALE, L.—The capitulum consists of 
_ about 100 to over 200 florets inserted on a receptacle only 5 to 7 
“mm. in diameter. «In each floret the tube is 3 to 7 mm. long and 
> the limb 7 to 15 mm. long, and in sunny weather the bapiéulum 
_ expands to form a bright yellow surface 30 to over 50 mm. in 
diameter. At night and in dull weather the capitulum closes up 
_ so completely that only the green involucral bracts and the dark 
_ outer surfaces of the limbs of the outermost florets remain visible. 
_ The honey rises into the upper part of the tube (which is nearly 
- filled by the style), and is therefore accessible to insects with very 
_ short proboscides. From each tube an anther-cylinder 23 to 5 
mm. long protrudes, and the style grows to a height of 3 to 5 mm. 
_ above the anther-cylinder. The projecting portion of the style is 
clothed with pointed hairs over its whole outer surface, which 
retain entangled among them the pollen that they have swept out 
of the anther-cylinder. The two branches of the style, which are 
_ closely covered over their whole inner surfaces with stigmatic 
_papiller, are 1} to over 2 mm. long; they bend outwards and 
curve so far back that the tip of each makes 1 spiral turns, and 
: accordingly, if insect-visits have not taken place and the sweeping- 
hairs are still covered with pollen, self-fertilisation must take place - 
‘to a great extent. 
Thus in the Dandelion we have a plant which, by the great 
conspicuousness of its flowers and the great abundance and ac- 
cessibility of its pollen and honey, attracts an immense variety of 
insects in sunny spring weather; but which has fully retained, or 
has again acquired, the possibility of self-fertilisation, since it 
_ begins to bloom so early that as a rule its first flowers receive no 
insect-visits, while its latest flowers are also liable to be left 
unvisited. 
Visitors : A. Hymenoptera—(a) Apide : (1) Apis mellifica L. §,s.ande.p., 
very ab, ; (2) Bombus silvarum, L. ? ; (3) B. terrestris, L. 9 ; (4). B. muscorum, 
oo; (5) B, lapidarius, L. ¢ ; (6) B. confusus, Schenck, ? ; (7) B, Barbutellus, 
