106 



THE INFLORESCENCE. 



The spike (Fig, 190) is represented by the Plantago, and the locusta by the common 

 Grass ; and they differ from each other, chiefly in that the former has the envelopes 

 of the flower distinct from each other, whilst in the latter the bracts foim the sole covering. 



Fig. 192. 



Fig. 193. 



Fig. 192. The inflorescence of the Arum, a, the spadix inclosed by the spat'ie; 6, the fleshy rachis, 

 or spadix denuded of flowers ; c, the spadix covered with sessile flowers. 



Fig. 193. A Capitulum in the Composite, o, florets of the ray ; b, florets of the disk; c, floret of 

 the ray detached; d, floret of the disk detached. 



The catkin, as in the "Willow, BO far resembles the locusta, that the coverings are not 

 distinct from each other ; but it differs inasmuch that the rachis with the flowers falls 

 in a single piece after fructification, whilst the rachis of the locusta is permanent. 

 The Spadix, as in the common Arum, is an inflorescence with a fleshy rachis, to which 

 the flowers are closely attached, and inclosed in the modified bract called a spathe, 

 Fig. 192. The Capitulum is a head of flowers sessile upon a receptacle, page 105 ; and in 

 the Compositae the flowers are divided into two classes, \hsflorets of the ray (Fig. 193 a), 

 which are usually ligulate or strap-shaped, and the florets of the disk, or centre, which 

 are commonly smaller, Fig. 193 b and d. The Gtomendw consists of a series of heads 

 in a common involucre. 



The second division, or those modes of inflorescence in which the flowers are each 

 supported by a pedicle or stalk, is an extensive field, and comprehends the most beautiful 

 flowering plants. It is divided into the Raceme, Fascicle, Corymb, Cyme, Panicle, and 

 Umbel. 



The Raceme is the simplest form, and consists of a series of stalked flowers arranged 

 on a common peduncle (Fig. 194), the pedicels being of nearly equal length. When 

 the lower pedicels are so much larger than the upper that the flowers are supported at 

 nearly an equal height, so as to form a kind of head, the terms Fascicle and Corymb are 

 applied, the former, as in the Sweet "William (Dianthus), when the expansion of tho 

 flower is from within outwards ; and the latter when from without inwards. Tho 

 remaining varieties of inflorescence are somewhat more complicated, since the stalks 01 

 pedicels are divided, and bear many flowers instead of one only. Thus the Panicle is a 



