272 



ANGIOSPERMAEDICO TYLEDONES 



than those of the five inner, and dehisce before anthesis, after which they com- 

 pletely shrivel up. Their pollen "is stored up in the hollow cone constituted by 

 the tip of the carina. The five inner stamens, which have so far remained short, 

 now begin to grow actively, and compress the pollen in the end of the carina. 

 During insect-visits they act as pistons, by which a string of pollen is squeezed 

 out from the carinal apex. When the weight of the visitor is removed, the alae 

 and carina return to their old position, so that further visits cause more pollen to 

 be extruded. At a later stage the stigma also protrudes, and visitors carrying 

 pollen from younger flowers will therefore effect crossing. As in Cytisus Laburnum, 

 automatic self-pollination is prevented, or at any rate hindered, by a circlet of stiff 

 erect hairs. 



Visitors. Herm. Miiller saw three po-cltg. bees. 1. Apis mellifica L. jjl, freq. ; 

 2. Bombus lapidarius Z. jjj, occasional; 3. Megachile circumcincta K. 5. The two 



first of these I noticed in Mecklen- 

 burg, and also Bombus terrester L. 5, 

 po-cltg. In Rugen I observed the 

 following. 



A. Hymenoptera. Apidae : 

 1. Apis mellifica L. 5, skg. and po- 

 cltg., with large masses of orange- 

 coloured pollen in its baskets; 2. Bom- 

 bus agrorum F. jjl, skg.and po-cltg. 

 B. Lepidoptera. Rhopalocera\ 3. 

 Argynnis paphia Z., skg., an unbidden 

 guest. 



Alfken saw the humble-bee 

 Bombus lapidarius Z. 5 in Bremen, 

 and Loew the following bees in Silesia 

 ('Beitrage,'p. 34). 



1. Bombus cognatus Steph. Jjj, 

 po-cltg.; 2. B. rajellus K. 5, do.; 3. 

 Megachile maritima K. $, do. 



Fig. 87. Lupinus luteus, L. (after Herm. Miiller). 

 (1) Stamens and pistil in the bud. (2) The same in the 

 mature flower. 1, 3, 5, 7, 9, the five inner, and 2, 4, 6, 8, 10, 

 the five outer stamens, x, stigma. 



658. L. angustifolius L. The blue flowers of this species are odourless and 

 devoid of nectar. Kirchner states that their mechanism agrees with that of the 

 last species ('Flora v. Stuttgart, p. 478). 



Visitors. I noticed the same bees in Mecklenburg as for the last species. 



659. L. polyphyllus Lindl. 



Visitors. Loew observed the following bees in the Berlin Botanic Garden. 



1. Andrena dorsata K. 5, transferring pollen pumped out from the carina to 

 the tibial and tarsal brushes of its hind-legs ; 2. Anthidium manicatum Z. $, po-cltg. 

 and trying to suck in spite of the absence of nectar, $ swarming about the flowers ; 

 3. Apis mellifica Z. jjl, cltg. the extruded pollen, and vainly skg. ; 4. Megachile 

 centuncularis Z. 5, do. ; 5. M. circumcincta K. 5, do. ; 6. M. ericetorum Lep. $, do., 

 $, vainly skg. ; 7. Osmia aenea Z. $, do. 



I saw the humble-bee Bombus lapidarius Z. J, vainly skg., at Kiel. 



