LEGUMINOSAE 317 



The nectar is also concealed in a remarkable way, for the claw of the vexillum 

 is so slender and bends so far upwards out of the short calyx, that it is possible 

 to look into the flower laterally between it and the stamens. It would, therefore, 

 appear as if insect visitors could easily steal nectar from the side, without setting 

 the flower mechanism in motion. This, however, is not the case, for the claw of 

 the vexillum bears a projecting triangular plate on the under-side of its base, and 

 by this the two nectar-passages are completely closed. Insects can only remove 

 this obstruction by thrusting in their heads under the vexillum (cf. Fig. 102). 



Visitors. Herm. Muller chiefly observed bees (12) and Lepidoptera (9) in 

 the Alps. Schulz noticed flowers perforated by humble-bees in Central Germany. 



Schmiedeknecht saw 3 bees in Thuringia: 1. Osmia aurulenta Pz. ; 2. O. 

 uncinata Gerst.; 3. O. xanthomelaena K. ( = 0. fuciformis Gerst.). 



Friese observed the following bees in Baden (B.), Hungary (H.), Switzerland (S.), 

 Thuringia (T.), and Trieste (Tr.). 



1. Megachile muraria Retz. (B.); 2. Osmia acuticornis Duf. et Perr. J (H.); 

 3. O. andrenoides Spin., infrequent ; 4. O. aurulenta Pz., freq. (B.) ; 5. O. gallarum 

 Spin., not infrequent (H., Tr.) ; 6. O. lepeletieri Per. ; 7. O. leucomelaena K., freq. 

 (H., Tr.); 8. O. rufohirta Lep. $ and S, skg. (H., T.); 9. O. uncinata Gerst. (S., T.); 

 10. O. xanthomelaena K. (T., S.). 



Loew saw Apis mellifica L. |jj, po-cltg., in Hesse, and, skg., in the Berlin Botanic 

 Garden, where he also noticed a humble-bee (Bombus lapidarius L. Ijj), do. (' Beitrage,' 



P- 53)- 



Ducke observed the following Apidae at Trieste. 



1. Eucera cinerea Lep. 5 and $; 2. Megachile (Chalicodoma) pyrenaica Lep. ; 

 3. Osmia andrenoides Spin. 5 and $, freq. ; 4. O. campanularis Mor. J ; 5. O. giraudi 

 Schmiedekn., not very infrequent; 6. O. fulviventris Pz. J, not infrequent; 7. O. 

 jheringi Ducke 5 and J, very freq. ; 8.0. longiceps Mor. <j> and $, not infrequent ; 

 9. O. pallicornis Friese 5 and 5, freq.; 10. O. rubicola Friese 5, freq., J, very 

 occasional ; 11. O. rufohirta Ltr. 5, freq., S, rather rare ; 12. O. solskyi Mor., rather 

 rare; 13. O. tergestensis Ducke <j> and S, infrequent; 14. O. tiflensis Mor. 5 and t, 

 occasional ; 15. O. tridentata Duf. et Perr., rare. 



MacLeod noticed 2 long-tongued bees and a Lepidopterid in the Pyrenees 

 (Bot. Jaarb. Dodonaea, Ghent, iii, 1891, p. 440). 



224. Desmodium Desv. 



751. D. canadense DC. 



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



A. Diptera. Syrphidae: 1. Melithreptus scriptus L., settling. B. Hymeno- 



ptera. Apidae: 2. Megachile centuncularis L. $, po-cltg. ; 3. M. fasciata Sm., $, do. 



C. Lepidoptera. Rhopalocera : 4. Pieris brassicae L., skg. 



225. Hedysarum L. 



Red nectar-yielding bee flowers, with simple valvular arrangement. 



752. H. obscurum L. (Herm. Muller, ' Alpenblumen,' pp. 254-5; Schulz, 

 'Beitrage,' I, p. 32, II, p. 210.) Hermann Muller says that for this species a 

 proboscis 9-10 mm. long is required to suck legitimately. The flower mechanism 

 is the simplest in the sub-order. When a humble-bee visits a flower, the stigma 



