120 



STKUCTUliAL BOTANY. 



Spear-grass, Catalpa. A thyme is a sort of compact, oblong, 01 

 pyramidal panicle, as iu Lilac, Grape. 



3(31. A head or capitulum is a sort of reduced umbel, having 

 the flowers all sessile upon 

 the top of the peduncle, as in 

 the Button-snake-root, Button- 

 bush, Clover. But the more 

 common examples of the ca- 

 pitulum are seen in the Com- 

 positse, where the summit of 

 the peduncle, that is, the re- 

 ceptacle, is dilated, bearing the 

 sessile flowers above, and scale- 

 like bracts around, as an in- 

 volucre. 



362. The capitulum of the 

 Composite is often called a 



,-^.A (\.^,, ,. f,.^, 446, Vernonia fasciculata flowers in a discoid 



COmpOUnd flOWer trOm itS re- head with an imbricated involucre. 447, A sinjrl* 



i ! ! . i flower remaining on the receptacle. 448f A fruit 



Semblance, the inVOlUCre an- crowned with the pappus. 449, MulKedium-a head 



450, A single flower remaining on the receptacle. 



swenng to a calyx, the rays to ^ A fruit with pappus. 

 the corolla. The flowers are called florets those of the outer 

 cArcle, florets of the ray, generally differing in form from those 

 of the central portions, the florets of the disk. 



363. Of terminal inflorescence the following varieties are 

 described: cyme, fascicle (verticillaster), and glomerule. 



448 



446 



luivrarc (452) of cyme; flowers numbered in the order of their development. 433, cyme fagtigiate. 

 454, Cyme half developed a scorpoid raceme. 



364. Cyme is a general term denoting any inflorescence with 

 centrifugal evolutions, but is properly applied to that level- 

 topped or fastigiate form which resembles the corymb, as in the 



