THE ARUM ORDER 389 



The flowers of palms are borne on a fleshy rachis which is 

 more or less branched and subtended by one or more large, 

 thick bracts. Such a fleshy spike whether simple or branched 

 is called a spadix,^ and the large bract subtending it a spathe."- 



Palms may be distinguished as iDoody plants, usually ivith 

 columnar trunks; large, plume-like or fan-shaped leaves; flowers 

 on a mostly branched spadixfornied within a spathe. 



146. The palm order (Palmales or Principes) includes only 

 the family of palms, which from their majestic appearance 

 and high importance were well called by Linnieus the Princes 

 of the Vegetable Kingdom. From other orders the ivoody 

 trunks, large and often compound leaves, mostly branched spadix, 

 conspicuous spathe, and the superior ovary with one or more 

 cells, and one or more ovules, Avill generally afford sufficient 

 marks of distinction. 



See formula of Palmales on pages 422, 423,. 



147. The arum family (Araceae) is exemplified by Acorus 

 (Fig. 167, page 174.) 



See formulas of Acorus and AraceiB on pages 422, 423. 



Although the members of this large family differ very much 

 in general appearance and in many details of structure, our 

 common sweet flag represents quite well their essential fea- 

 tures. As in the palms, there is a spadix, although it is alwa3^s 

 simple; and there is a spathe which, unlike that of the sweet 

 flag, is generally highly colored. In our example, moreover, 

 the spadix, while appearing as if lateral, is in reality terminal, 

 having been pushed to one side by the peculiar elongated 

 spathe which appears to continue the stem. 



The family may be defined as consisting of mostly perennial 

 herbs, sometimes aromatic, often ill-smelling or acrid; with 

 leaves of varied form., often netted-veined; and floivers in a sim- 

 ple spadix, subtended by a more or less petaloid spathe. 



148. The arum order (Arales or Spathiflorae) comprises 



^ Spa'dix < Gr. spadix, a palm-branch. 



- Spathe < Gr. spathe, a broad flat blade or spatula. The exclama- 

 tion marks used in the formulas after I and B indicate, as usual, the 

 fleshy character, and the oblique line after B, its involucral nature. 



