LEGUMINOSAE 



267 



643. G. sagittalis L. Kirchner ('Flora v. Stuttgart/ p. 474) states that, 

 like G. germanica, this species possesses a simple non-explosive valvular mechanism. 

 The column, made up of style and stamens, protrudes from the carina during insect- 

 visits, moving back again when the pressure is removed. The anthers dehisce 

 in the bud, and as the slightly up-curved style extends but little beyond them 

 at this stage the stigma is self-pollinated. After the vexillum has become erect, 

 the style, which is still bent slightly upwards, projects about 1 mm. beyond the 

 anthers, so that when a bee settles on the flower the stigma first projects from 

 the carina and touches its ventral surface. The second flower visited by an insect 

 is therefore cross-pollinated. Should considerable pressure be exerted, the carina 

 remains depressed as in G. germanica. 



Visitors. Kirchner observed undetermined species of Apidae. Schenck saw 

 two sternotribous bees, i.e. Megachile circumcincta K. and Trachusa serratulae Pz. 



644. G. anglica L. In this species, which was first thoroughly described by 

 Hermann Muller ('Fertilisation,' pp. 192-3), the opposite tensions of style and 

 stamens on the one hand, and of the carina and alae on the other, are much less 

 pronounced. The carina and 



alae sink down but little when 

 explosion takes place, and 

 only the style curves upwards, 

 its tip at the same time curling 

 inwards. 



Visitors. Herm. Muller 

 observed the honey-bee as 

 a visitor. This almost ex- 

 clusively visited unexploded 

 flowers, assuming a position 

 as if it would suck concealed 

 nectar from their bases, and 

 filling its pollen-baskets with its second legs. Herm. Muller also repeatedly 

 saw two short-tongued bees po-cltg., i.e. Andrena fulvicrus K. 9 and Halictus 

 cylindricus F. 9. 



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



1. Andrena nigro-aenea K. 9, infrequent, po-cltg.; 2. A. convexiuscula K. 9, 

 po-cltg.; 3. Apis mellifica L. ijj, do.; 4. Bombus muscorum, F. 9; 5. B. terrester 

 L. 9; 6. Halictus flavipes F. 9, freq., po-cltg.; 7. H. leucopus K. 9 ; 8. H. rubi- 

 cundus Chr.%, freq., po-cltg.; 9. Osmia uncinata Gerst. 9, one individual, po-cltg.; 

 10. Nomada alternata Pz. 9 (H.); 11. N. succincta Pz. 9 (H.). 



In Amrum and Fohr, I only saw the honey-bee ('Bl. u. Insekt. a. d. nordfr. 

 Ins.,' p. 152). 



In Fohr and Sylt, I observed a moth (Zygaena filipendulae L.), as an unbidden 

 guest, vainly trying to suck. 



645. G. pilosa L. The flower mechanism of this species agrees completely 

 with that of G. anglica. It was first described by Delpino ('Ult. oss.,' pp. 48-52). 

 He found that the flowers are self-sterile. 



Fig. 84. Genista anglica, L. (after Herm. Muller). (i) Un- 

 visited flower, seen from the side. (2) The same, seen from the front. 

 (3) Right ala, seen from the inner side. (4) An exploded flower, with 

 the style curved back less than usual. (5) A flower that has exploded 

 normally, seen from the left, e, tip of style ; J", stigma ; A, alar fold. 



