LEGUMINOSAE 



273 



660. L. albus L.— Delpino states that this species essentially agrees with 

 L. luteus (' Ult. OSS.,' pp. 46-7). 



661. L. hirsutus L. — 



Visitors.— Schletterer saw the humble-bee Bombus terrester Z. at Pola. 



201. Ononis L. 



Generally red, rarely white or yellow, nectarless bee flowers, with a pumping 

 arrangement from which threads of pollen are extruded. Bentham says that apetalous 

 cleistogamous flowers are often present in South European species. 



662. O. spinosa L. (Herm. Muller, 'Fertilisation,' pp. 174-5; Kirchner, 

 'Flora V. Stuttgart,' pp. 478-9; Knuth, ' Bl. u. Insekt. a. d. nordfr. Ins.,' pp. 57-8; 

 Loew, 'Blutenbiol. Floristik,' p. 392; Warnstorf, Verh. bot. Ver., Berlin, xxxviii, 

 1896.)— The flowers of this species are rose-red in colour, more rarely white, without 

 nectar or nectar-guides. 



Hermann Muller describes 

 the alae as flat plates, that 

 are separate below but 

 converge above to en- 

 sheath the upper part of 

 the carina, with which they 

 interlock by means of a 

 pointed process on either 

 side, that projects forwards 

 and downwards internal to 

 the upper alar margin, 

 and fits into a deep carinal 

 fold. There is also a 

 basal lappet projecting 

 backwards from the upper 

 margin of each ala, and 

 resting upon the sexual 

 column, without touching 

 its fellow. 



The ten cohering filaments are somewhat thickened just below the anthers, 

 the five outer ones much more strongly than the others. The anthers of the five 

 inner stamens, on the other hand, produce a larger quantity of poUen. Before 

 anthesis, the anthers extend to the base of the hollow cone formed by the tip of 

 the carina, completely fill this with pollen, and then shrivel up. The stigma is 

 situated a little below the carinal apex. 



The upper margins of the carinal petals are at first united for the whole of 

 their extent, except that a small opening is left at the tip. If now the carina is 

 slightly depressed, the thickened ends of the filaments are pushed further into the 

 pollen-chamber, and a corresponding amount of pollen is squeezed out. The carina 

 returns to its original position when the pressure ceases. With repeated depression 

 the united upper margins of the carinal petals are split apart, when stamens and 



Fig. 88. Ononis spinosa, L. (after Herm. Miilleri. (i) Reproductive 

 organs of a bud. (2) The same of a mature flower (x 7). (3) Flower 

 after removal of calyx and vexiilum, seen from the side. (4) Some 

 stamens, more highly maf^nified, to show the difference between the outer 

 and inner filaments as regards thickening. (5) Left ala seen from the 



inner side, with the upper margin directed downwards. (6) Outer surface 

 of the same, a and 6, outer and inner stamens ; c, pollen in the tip of the 

 carina, seen by transparency ; d, pointed alar process ; e, alar lappet. 



