268 



ANCIOSPERMAE—DICOTYLEDONES 



Visitors. — Hem:. Muller ('Fertilisation,' p. 193) in Westphalia, and myself in 

 Fohr and Amrum, observed the honey-bee. 



At Wiesbaden Rfissler noticed the moth Threnodes poUinalis S. V. as an 

 unbidden guest. 



196. Ulex L. 



As the last genus. 



646. U. europaeus L. (Ogle, Pop. Sci. Rev., London, ix, 1870, pp. 164-5; 

 Heinsius, Bot. Jaarb. Dodonaea, Ghent, iv, 1892, pp. loi et seq. ; Knuth, ' Bloemen- 

 biol. Bijdragen.') — Ogle states that the flower mechanism of this species agrees with 

 that of G. tinctoria, and Kerner also describes it as an explosive arrangement. 

 But, according to my own observations, the contrary tensions of stamens and style 

 on the one hand, and carina and alae on the other, are not so strong, so that the 

 mechanism much more closely resembles those of G. anglica and G. pilosa. 



Fig. 85. U/£x europaeus, L. {from nature). A. Exploded flower ; s, stigma. 5, C. An ala, seen 

 from within and without. D. Stamens and pistil enclosed in the carina, and seen by transparency. The 

 style is bent like a spring, so that the stigma is pressed against the cohering upper edges of the carina! 

 petals. B. The same, removed from the carina. 



The carina and alae are only united together at one point on the upper side 

 of their claws, where some of the epidermal cells interlock, and an alar projection 

 fits into a carinal pit on either side. The union is so slight that the petals can 

 easily be separated without tearing. 



Although explosion is but feeble, the pollen is so completely discharged on 

 to the ventral surface of the visiting bee, that when this has flown away scarcely 

 a single grain can be found upon the anthers. 



Visitors. — In the island of Fohr (' Bl. u. Insekt. a. d. nordfr. Ins.,' p. 85) I saw 

 numerous well-developed fruits, indicating insect-visits, although I never actually 

 observed these. The size of the flowers suggested that humble-bees were the 

 pollinators. And I actually noticed Bombus terrester Z. 5 as a visitor at Kiel 

 (May 9 and 23, 1896). I also saw Meligethes as an unbidden guest. In Flanders, 

 ]\IacLeod noticed Apis, Bombus terrester L. 5, 2 Halictus, and 2 flies (the last four 

 only on exploded blossoms) (Bot. Jaarb. Dodonaea, Ghent, vi, 1894, p. 329). 



Burkill observed the following on the Yorkshire coast ('Fertlsn. of Spring 

 Fls.'V— 



