INDETERMINATE INFLORESCENCE. 



211 



383. Before illustrating these, one or two terms, of common oc- 

 currence, may be defined. A flower which has no stalk to support 

 it, but winch sits directly on the stem or axis it proceeds from, is 

 said to be sessile. If raised on a stalk, this is called its PEDUNCLE. 

 If the whole flower-cluster is raised on a stalk, this 



keeps the name of peduncle, or common peduncle (Fig. 

 307, p) ; and the stalk of each particular flower, if it 

 have any, takes the name of Pedicel or partial 

 peduncle (])'). The portion of the general stalk along 

 which flowers are disposed, is called the axis of in- /O^f 

 florescence, or, when covered with sessile flowers, the 

 rhachis (backbone), and sometimes (as when thick 

 and covered with crowded flowers) the receptacle. 

 The leaves of a flower-cluster generally are termed 

 Bkacts. • But when we wish particularly to distin- 

 guish their sorts, those on the peduncle, or main axis, 

 and which have a flower in their axil, take the name 

 of Bracts (Fig. 307, b) ; and those on the pedicels or 

 partial flower-stalks, if any, that of Bractlets or 

 Bracteoles (b 1 ). The bracts are often reduced to 

 a minute size, to as to escape ordinary notice : they 

 very frequently fall off when the flower-bud in their 

 axil expands, or even earlier ; and sometimes, as in 

 the greater part of the Mustard family, they altogether 

 fail to appear. 



384. A Raceme (Fig. 307, 308, 315) is that form of flower-cluster 

 in which the flowers, each on their own footstalk or pedicel, are 

 arranged along a common stalk or axis of infloresence ; as in the 

 Lily of the Valley, Currant, Choke-Cherry, Barberry, &c. The 

 lowest blossoms of a raceme are of course the oldest, and therefore 

 open first, and the order of blossoming is ascending, from the bot- 

 tom to the top. The summit, never being stopped by a terminal 

 flower, may go on to grow, and often does so (as in the Snowberry, 

 Shepherd's Purse, &c), producing lateral flowers one after another 

 throughout the season. In the raceme, the axis of inflorescence is 

 more or less elongated, and the pedicels are about equal in length. 



385. A Corymb (Fig. 309, 319) is the same as a raceme, except 

 that the lower pedicels are elongated, so as to form a level-topped or 

 slightly convex bunch of flowers ; as in the Hawthorn, &c. 



FIG 307. A Raceme, with a general peduncle (/>), pedicels (//), bracts (6), and bractlets (V). 



