EVOLUTION OF THE INFLORESCENCE. 555 
process and the absence of bracts suggest an inflorescence which has under- 
gone a considerable reduction in the number of its flowers, and a total 
suppression of leaf-organs. It is, in fact, a flower-cluster, by no means in 
the making, but rather one much on the wane. 
Ononis Natriz.—ln this species the reduction has gone farther (fig. 8, B). 
Only a single flower is borne in each leaf-axil, and not a cluster, but the 
manner in which this flower is attached shows unmistakable evidence of 
having been derived by reduction from an inflorescence like that of the 
foregoing species. The flower, in fact, is not borne directly on the main 
axis (peduncle) issuing from the leaf-axil, but on a secondary axis (pedicel) 
arising laterally from the former. The peduncle is produced beyond the 
point, where the pedicel is emitted, into a short sterile process. Thus the 
solitary flower is in reality an axillary raceme reduced to a single bloom, 
instead of to three as in the previous species. 
Fig. 8. 
A. Axillary raceme of Ononis rotundifolia, consisting of three flowers: p., prolongation 
of axis beyond uppermost flower. 
B. Axillary raceme of Ononis Natrix, reduced to a single flower. 
C. Solitary axillary flower of Ononis arvensis, derived from 1 through suppression 
of peduncle. 
Ononis arrvensis.—The axillary solitary flower possessed by this species 
appears to be borne directly on a short stalk proceeding from the leaf-axil 
(fig. 8, C). Without a comparison with the foregoing species, this flower 
might have been considered as primitively solitary and axillary. The 
evidence, however, seems strongly in favour of regarding it as an instance 
of a solitary axillary flower derived from an axillary inflorescence through 
reduction, The short flower-stalk probably represents the pedicel in Ononis 
Natria, the peduncle having been completely suppressed. 
Axillary racemose inflorescences are of common occurrence in the her- 
baceous and shrubby Papilionacez ; hence, whenever single axillary flowers 
occur, it may be supposed that they have arisen through reduction from 
axillary inflorescences, even though the steps may not be so apparent as in 
