

COMPOSITAE 697 



1660. C. albida Vill. The florets of this species are of a yellowish colour. 

 Visitors. MacLeod (Pyrenees) observed 4 bees, a Lepidopterid, 4 beetles, 



a Syrphid, and 2 Muscids. 



1661. C. grandiflora Tausch. (Kerner, 'Nat. Hist. PI.,' Eng. Ed. 1, II.) 

 Kerner has observed that when the heads of this species close in the evening they are 

 used as quarters for the night by some of the smaller beetles (Cryptocephalus, Meli- 

 gethes) and bees (Panurgus ursinus Lir.), for at that time their interior is warmer 

 than the surrounding air. These insects leave their refuge at sunrise, and being 

 dusted with pollen transfer this to other flowers which they visit. 



Kerner has also noticed that autogamy is effected by the shrivelling and spiral 

 twisting of the stylar branches, which are thus brought into contact with the pollen of 

 their own florets. 



504. Hieracium L. 



Florets usually bright-yellow to golden-yellow in colour, rarely orange. The 

 part of the style which projects from the anther- cylinder is completely covered with 

 pointed spinose sweeping-hairs, while the inner surfaces of the stylar branches are 

 beset with stigmatic papillae. Kerner states that geitonogamy takes place as in 

 Crepis, and that as in that genus automatic self-pollination is rendered possible 

 by subsequent elongation of the corolla. 



Ostenfeld and Raunkjaer (Bot. Tids., Kjobenhavn, xxv, 1902, pp. 409-13) 

 castrated the flowers of a number of species by the method used in the case of 

 Taraxacum (cf. 683), and obtained parthenogenetically formed fruits, though no 

 germinating pollen-grains were observed on the stigmas. In the case of one 

 species (H. hyparcticum Almq) plants were raised from such fruits. 



1662. H. Pilosella L. (Herm. Miiller, 'Fertilisation,' pp. 355-6, 'Weit. 

 Beob.,' p. 93, ' Alpenblumen,' p. 460 ; Knuth, ' Bl. u. Insekt. a. d. nordfr. Ins.,' 

 pp. 98, 162, ' Bloemenbiol. Bijdragen'; de Vries, Ned. Kruidk. Arch., Nijmegen, 2. Ser., 

 2. Deel, 1875; MacLeod, Bot. Jaarb. Dodonaea, Ghent, iii, 1891, v, 1893; Loew, 

 'Bliitenbiol. Floristik,' pp. 390-8.) Cf. Fig. 210. Hermann Miiller states that the 

 heads of this species contain 42-64 florets of a bright sulphur-yellow colour, 

 the marginal ones being usually streaked with red. During sunny weather the 

 heads expand (according to Linnaeus from 7 a.m. to 3 p.m.) to a diameter of 

 20 mm. They are closed in the evening and at night, also during dull weather. 

 The florets increase in size from the centre to the periphery; their corolla-tube 

 is 3-6 mm. and their ligule from 4-8 mm. long. In the first stage of anthesis 

 the sweeping-hairs of the style brush the accumulated pollen out of the anther- 

 cylinder, after which the stylar branches curve back to such an extent that automatic 

 self-pollination becomes possible. 



Visitors. Alfken and Hoppner (H.) observed the following at Bremen. 



A. Coleoptera. Bupreslidae; 1. Anthaxia quadripunctata ., freq. B. Di 

 ptera. Syrphidae: 2. Cheilosia soror Zett., skg. ; 3. Eristalis tenax Z., freq., skg. ; 



4. Helophilus trivittatus F., very common, skg. C. Hymenoptera. (a) Apidae : 



5. Andrena albicans Miill. $ and &, rare; 6. A. albicrus K. $, freq., skg.; 7. A. 

 argentata Sm. 5, rare, po-cltg. ; 8. A. chrysopyga Schenck $, rare ; 9. A. convexiuscula 

 K. 5 and $, do.; 10. A. fulvago Chr., very rare, 5 skg., po-cltg., 4" skg.; n. A. 



