NUDIFLOR^ 361 



Portland Arrowroot has been used as sago, but the 

 tuber is acrid and it is not easy to get rid of this 

 property, and the tuber is poisonous. 



Arum maculatum. — In Fig. gg are sJiown the 

 berries with the remains of the spathe below. 



Sweet Flag (Acorus Calamus). 



Being regarded formerly as a cure for diseases of 

 the eye, the first name, derived from the Greek, a, 

 without, and kore, pupil, is not inappropriate. The 

 second name Calamus^ a reed, refers to its reed-like 

 habit. The English name chosen refers to its flag- 

 like habit, and to its sweet scent, when the leaves 

 are rubbed between the fingers. 



There appears to be some doubt as to whether the 

 plant is indigenous in all parts of the British Isles, 

 where it occurs. But in England it appears to be 

 indigenous and more common south of Central 

 England, whilst in Scotland and Ireland it is only 

 naturalised.* It is common in Norfolk and Suffolk. t 



Ponds, ditches, streams, canals, and rivers, form 

 the habitat of the Sweet Flag. It occurs in the 

 fresh-water aquatic formation in waters relatively rich 

 in mineral salts, in slowly flowing waters, in the reed 

 swamp association, either closed or open. 



The habit is erect. The rhizome is sympodial. 

 The rootstock is thick, shortly creeping. The leaves 



* t Where it may have been introduced owing to the useful 

 proptrties it possesses or more rarely for ornament. 



