180 



INDEFINITE INFLOEESCENCE. 



it gives rise to other forms of indefinite inflorescence. When 

 the axis is so shortened that the secondary axes arise from a 

 common point, and spread out as radii of nearly equal length, each 

 ending in a single flower, or dividing again 

 in a similar radiating manner, an Umbel is 

 produced, as in figs. 261 and 262. In fig. 

 261 the floral axes, a a' a, end in simple 

 umbels, o' o' o', and the' umbels are called 

 stipitate or stallced ; while in, fig. 262 the 

 primary floral axis, a, is very short, and the 

 secondary axes, a a, come off from it in 

 a radiating or umbrellarlike manner, and 

 end in small umbels, o", which are called 

 partial umbels or vmibellules, to distinguish 

 them from the general umbel arising from 

 the primary axis. This inflorescence is 

 seen in Hemlock, and other allied, plants, which are hence called 

 Umbelliferous. ' 



If there are numerous flowers on a flattened, convex, or slightly 



Fig. 264. 



Fig, 26B. 



Fig. 266. 



Fig. 2&r. 



concave receptacle, having either very short pedicels or none, a capi- 

 tulum (head) or anthodium (avhg, a flower, o5o'e, a way or method), 



Fig. 264. Capitulum of Scorzonera hispanica cut verticaUy. r. Receptacle, Phoran- 

 thiuin, or the flattened and depressed apex of the peduncle, bearing the florets, /, which 

 are surrounded by bracts, b. Fig. 265. Inflorescence of Dipsacus sylvestris. Capi- 



tulum, or head of flowers, each of which is surrounded by long pointed bracts. The 

 flowers are evolved in a centripetal manner, e i, The first expanded, followed by those at 

 e m, while those at the apex, e s, are in bud. Fig. 266. Inflorescence of Dorstenia Con- 

 trayerva, consisting of a broad slightly concave receptacle, r, in which numerous male 

 and female flowers, /, are placed. Fig. 267. Inflorescence of Fig (Fi(MS Carica), showing 

 the hollow receptacle, r, or peduncle (which is popularly called tlie fruit), covered with 

 flowers, /, of various kinds. 



