MONOCOTYLEDONS AND DICOTYLEDONS 



245 



modified in a remarkable way into a club-shaped or tail-like 

 often brightly colored affair. This singular flower-cluster 

 with its fleshy axis is called a spadix. The flowers often 

 include but one sort of sporophyll, and staminate and 

 pistillate flowers hold different positions upon the spadix 

 (Fig. 226). 



The spadix is enveloped by a great bract, which sur- 

 rounds and overarches like a large loose hood, and is called 

 the spathe. The spathe is exceedingly 

 variable in form., and is often conspic- 

 uously colored, forming in the Calla- 

 lily the conspicuous white part, within 

 which the spadix may be seen, near the 

 base of which the flowers are found. 

 In Jack-in-the-pulpit (Fig. 225) it is 

 the overarching spathe which suggests 

 the "pulpit." The spadix and spathe 

 are the characteristic features of the 

 group, and the spathe is variously 

 modified in form, structure, and color 

 for insect pollination, as is the peri- 

 anth of other entomophilous groups. 



Aroids are further peculiar in hav- 

 ing broad net-veined leaves of the Di- 

 cotyledon type. Altogether they form 

 a remarkably distinct group of Mon- 

 ocotyledons. 



135. Lilies. The lily and its allies are usually regarded 

 as the typical Monocotyledon forms. The perianth is 

 fully developed, and is very conspicuous, either undifferen- 

 tiated or with distinct calyx and corolla, and the flower is 

 well organized for insect pollination. The flowers are either 

 solitary or few in a cluster and correspondingly large, or in 

 more compact clusters and smaller. In any event, the 

 perianth is the conspicuous thing, rather than spathes or 



glumes. 



34 



FIG. 226. Spadix of an 

 Arum, with spathe re- 

 moved, showing cluster 

 of naked pistillate flow- 

 ers at base, just above 

 a cluster of staminate 

 flowers, and the club- 

 shaped tip of the spa- 

 dix. After WOSSIDLO. 



