282 ANGIOSPERMAE—DICOTYLEDONES 



678. I. speciosa. — This species, according to Henslow (J. Linn. Soc, Bot., 

 London, ix, 1867), possesses the flower mechanism described by Hildebrand [vide 

 supra), and represents it as expressly adapted to secure cross-pollination. 



679. I. macrostachya Vent. — 



Visitors. — Delpino saw Bombus italicus (' Ult. Oss.,' p. 54). 



205. Parochetus Buch.-Ham. 

 Kuhn states that cleistogamous flowers occur in this genus. 



206. Melilotus Tourn. 



Yellow or white bee flowers, arranged in racemes. They secrete nectar and 

 smell like cumarin. There is a simple valvular arrangement by which the stamens 

 and pistil are caused to protrude from the carina so long as pressure is exerted 

 by visitors (bees). 



680. M. altissima Thuill. (=M. officinalis WiUd>i. (Herm. Mflller, 'Ferti- 

 lisation,' pp. 180-1; Kerner, 'Nat. Hist. PI.,' Eng. ed. i, II; Schulz, ' Beitrage,' II, 

 p. 208; MacLeod, Bot. Jaarb. Dodonaea, Ghent, vi, 1894, pp. 338-9; Loew, ' Blii- 

 tenbiol. Floristik,' pp. 392, 395; Knuth, ' Bloemenbiol. Bijdragen.') — The bright 

 golden-yellow flowers of this species exhale an odour of cumarin. Hermann Muller 

 states that the calyx is only 2 mm. long, and moderately wide, so that the nectar 

 can be reached by short-tongued insects. The alae and the carina are partially 

 fused together on either side, so that both are depressed when the flower is visited 

 by an insect, and simultaneously return to their original position when the pressure 

 is removed. The latter movement is due to the fact that there are two finger- 

 like processes directed backwards and inwards on the upper basal angle of the 

 alae, and embracing the column formed by the stamens and pistil. These processes 

 slide along the upper side of the column during depression, returning to their 

 original position when the pressure is removed, and guiding the carina and alae 

 back to theirs. 



As the stigma projects beyond the anthers, cross-pollination is secured by 

 insect-visits ; failing these, automatic self-pollination is difficult, but Kerner states 

 that it is effective. 



Visitors. — Herm. Muller observed the following. — 



Hymenoptera. (a) Apidae: 1. Andrena dorsata K. 5, skg. and po-dvg. ; 

 2. Apis mellifica L. 5, very freq., do. ; 3. Coelioxys quadridentata L. S, skg. ; 4. 

 Heriades truncorum L. 5, po-cltg. ; 5. Osmia sp. (b) Sphegidae : 6. Ammophila 

 sabulosa Z. S, skg. (c) Tenthredinidae : 7. Tenthredo sp., vainly searching for 

 nectar. 



In Schleswig-Holstein I saw only the honey-bee, in great numbers, po-cltg. 

 and skg. 



Loew observed a short-tongued bee (Halictus zonulus Sm. 5) po-cltg. in Central 

 Germany, and the following at Warnemiinde. — 



A. Hymenoptera. (a) Apidae: i. Andrena pilipes Z'. 5, po-cltg. ; 2. Anthidium 

 strigatum Ltr. 5, do.; 3. Coelioxys quadridentata L. $, skg.; 4. C. elongata Lep. 5, 

 do. ; 5. C. rufocaudata Sm. J, do. ; 6. Hahctus rubicundus Chr. j, po-cltg. ; 7. Osmia 



