AROIDE^ 169 



A. maculatum, L., Cuckoo-Pint, Lords-and-Ladies ; 

 leaves spotted, appearing in the spring, spadix violet; 

 hedge -banks; Switzerland, Pyrenees. A. italicum, 

 Mill. ; spadix yellow, leaves not always spotted ; Ticino, 

 Pyrenees. 



2. Calla, L. 



Spadix entirely covered with flowers ; anthers on long 

 filaments. 



C. palustris, L. ; leaves cordate, spathe white inside ; 

 marshes ; Lucerne, Vosges. 



3. ACORUS, L. 



Perianth-segments membranous ; stamens 6. 

 A. Calamus, L. ; Sweet -Flag; leaves ensiform ; wet 

 places, rare. 



Order XCIX.— LEMNACEiE. 



Perianth o ; stem and leaves reduced to floating green 

 disks. Aquatic plants ; not alpine. 



I. Lemna, L. 



Our four species of Duckweed, L. minor, L., gibba, 

 L., trisulca, L., and polyrhiza, L., all occur in Switzer- 

 land, though the first only is common; they are very 

 rarely seen in flower. 



2. WOLFFIA, Hork. 



An extremely minute floating plant, resembling Lemna, 

 but much smaller ; perianth o. 



W. arhiza, Wimm. ; the smallest European flowering 

 plant ; Switzerland, very rare. 



