1894.] 



Species of Medicago L. in England. 



151 



Winds, except by knocking spike against spike, are not likely 

 to explode the flower, as only very violent shaking effects it. 



Conclusion. Comparing the number of species in these lists 

 with those given by Miiller, we get the following table : — 



Hymenoptera 



Lepido- 

 ptera 



Diptera 



Coleo- 

 ptera 



M. sativa 



Germany 

 England 



M. falcata 

 Germany 

 England 



M. lupulina 

 Germany 

 England 



.SI'S 





Other 

 Insects 



■a a. 



oS 



Total 

 no. of 

 Species 



27 

 31 



28 



7 



12 

 56 



From this it appears not unlikely, as might be expected, that 

 flies take in England the place which other more special- 

 ised insects occupy in Germany^ 



The second table indicates the number of individuals ob- 

 served to visit the flowers. The Hive-bees were too numerous 

 and too assiduous to permit of accurate counting for M. sativa and 

 M. sylvestris ; they were therefore estimated in these two cases. 

 It is impossible to state the number of individual flowers 

 visited. 



The last two lines show that, except for Halictus, there is but 

 little difference between Cambridge and Scarborough in the rela- 

 tive proportions of the insect visitors to M. lupulina. 



Finally, the mechanism of the flower of Medicago seems nearer 

 to that of Trifolium than of Melilotus ; for the basal processes do 

 not press on the staminal tube. The combining processes possess 

 a new function — a necessary consequence of the new explosive 

 property of stamens, which we do not find in other genera of 

 Trifolieae. With regard to the stigma, it is such an easy transition 

 from the normal glandular form to one in which the secretion is 

 hindered and receptivity only brought about by injury, that we 



' This contains all the 'allotropous' or short-tongued flies. Cf. E. Loew, 

 Beitriige zur bllithenbiologischen Statistik. Verhandl. d. Bot. Vereins d. Provinz 

 Brandenburg, xxxi. 1889, p. 1. 



2 Further observations made with Mr J. C. WiUis near PKnlimmon and by myself at 

 Scarborough support this ; as also do Scott Elliot's observations in South Scotland, 

 Flora of Dumfrieshire, Parts I. and II., Trans, and Journal of Proceedings of Dum- 

 friesshire and Galloway Nat. Hist, and Antiquarian Soc. 1891 — 92. 



