SPECIAL FOKMS OF INFLORESCENCE. 



119 



356. The spadix is a thick, fleshy rachis, with flowers closely 

 sessile or imbedded on it, and usually with a spathe, as in 

 Calla (432), or without it, as in Golden-club (436). 



357. The catkin or ament is a slender, pendent spike with 

 scaly bracts subtending the naked, sessile flowers, all caducous 

 (falling) together, as in Birch, Beech, Oak, Willow. 



358. The raceme is a rachis bearing its flowers on distinct, 

 simple pedicels. It may be erect, as in Hyacinth, Pyrola ; or 

 pendulous, as in Currant, Blackberry. The corymb differs from 

 the raceme in having the lower pedicels lengthened so as to 

 elevate all the flowers to about the same level. The corymb 

 often becomes compound by the branching of its lower pedicels, 

 as in Yarrow. 



444 445 



444, Staphylea trifolia a pendulous, paniculate cyme. 445, Catalpa a panicle. 



359. An umbel consists of several pedicels of about equal 

 Ir.ngth radiating from the same point the top of the common 

 peduncle, as Milk-weed, Ginseng, Onion. When the pedicels of 

 an umbel become themselves umbels, as in Caraway and most 

 of the Umbelliferae, a compound umbel is produced. Such sec- 

 ondary umbels are called umbellets, and the primary pedicels, 

 rays. 



360. The panicle is a compound inflorescence formed by the 

 irregular branching c f the pedicels of the raceme as in Oats, 



