Acorus Araceae 277 



23. ARACEAE Neck. Arum Family 



Spadix cylindrical without an obvious spathe, borne on the side of a leaf like scape; 

 flowers perfect, perianth present; leaves linear; rootstocks and leaves aromatic. . . . 



694. Acorus, p. 277. 



Spadix subtended by a spathe; leaves broader than the linear type. 



Spadix globose, enveloped in a very fleshy, ovoid spathe; flowers perfect, perianth 

 present; mature leaves large, simple, mostly 1.5-2.5 dm wide, malodorous when 



bruised 708. Symplocarpus, p. 277. 



Spadix longer than wide; flowers without a perianth; leaves, if undivided, generally 

 less than 1.5 dm wide. 

 Spathes flat, divaricate, white within; spadix short-cylindric, the whole surface 



covered with flowers, at least the lower ones perfect 710. Calla, p. 277. 



Spathes convolute, at least below, enveloping the spadix; spadix elongate; flowers 

 monoecious or dioecious. 



Leaves sagittate, simple; flowers covering the whole surface of the spadix 



747. Peltandra, p. 278. 



Leaves not sagittate, more or less divided into 3 or more segments; upper part 

 of spadix not flower-bearing 786. Arisaema, p. 278. 



694. ACORUS L. 



1. Acorus Calamus L. Sweetflag. Calamus. Map 570. Widely dis- 

 tributed in the state, mostly in noncalcareous springy places along streams 

 and about lakes. Local in the lake area and in the Tipton Till Plain and 

 very local to rare in the unglaciated area. It is usually found in large 

 colonies, sometimes covering acres in old stream beds. This species 

 flowers and fruits throughout the state. In medicine, the rootstock is 

 known as calamus. 



N. S. to Ont. and Minn., southw. to Fla. and Tex. ; also in Eurasia. 



708. SYMPLOCARPUS Salisb. 



1. Symplocarpus foetidus (L.) Nutt. (Spathyema foetida (L.) Raf.) 

 Skunkcabbage. Map 571. In noncalcareous springy places throughout the 

 state although there are few records from the southwestern and un- 

 glaciated parts. While the habitat of this species is usually somewhat 

 wetter than that of sweetflag, but otherwise similar, I have never seen 

 them growing together. Acorus Calamus, however, prefers sunlight while 

 this species prefers dense shade. The colonies vary in size, usually occupy- 

 ing all the available space in the habitat. 



N. S. to Minn., southw. to Ga. and Iowa. 



710. CALLA L. 



1. Calla palustris L. Wild Calla. Map 572. This species still occurs 

 in La Porte County in a decadent tamarack bog about six miles west of 

 La Porte and in Noble County in sec. 12 of Washington Township where 

 it is found in mucky soil among Cephalanthus on the border of a Chamae- 

 daphne bog. It was reported from two places in Noble County by Van 

 Gorder but at both of these stations the habitat has been destroyed by 

 drainage. It was reported in 1913 from La Porte and St. Joseph Counties 



