486 THE AETTM FAKlIiT. 



meter ; the lower female heads are full 6 lines in diameter, glabrous, with 

 the long, linear points of the stigmas very prominent. 



On the margins of ponds, lakes, and streams, almost all over Europe and 

 Russian Asia, and a poi'tion of North America, but scarcely reaching the 

 Arctic Circle. Extends all over Britain. Fl. summer. 



2. Simple Sparganium. Sparganium simplex, Kuds. 



(Eng. Bot. t. 74.5.) 



E-ather smaller than the branched S., with narrow leaves ; the flower- 

 heads much fewer, at considerable distances from each other along the 

 simple summit of the stem ; all sessile except the lowest female, wliich is 

 often on a peduncle of 1 to 2 inches. Flowers as in the branched S. 



In similar situations, and nearly as widely distributed as the branched S., 

 but not quite so common. Not unfrequent in England and Ireland, but 

 more rare m Scotland. Fl. summer. 



3. Floating Sparganium. Sparganium natans, Linn. 



(Eng. Bot. t. 273. S. minimum, Bab. Man.) 

 An aquatic plant ; the weak stems ascending to the surface of the water, 



on which the long, narrow leaves float. Flower-heads very few, with long, 



linear bracts ; the 2 or 3 lowest ones female, and usually stalked. Fruiting 



heads smaller than in the two last species, and the styles or points to the 



fruits vei-y much shorter. 



In lakes and pools, in northern and Arctic Europe, Asia, and America ; 



and in the high mountain-ranges of southern Europe and central Asia. 



lu Britain, more frequent in Scotland and Ireland than in England. FL 



summer. 



LXXV. THE ARUM FAMILY. AEOIDE^.. 



Herbs, with the rootstock often tuberous but not bidbous ; 

 the veins of the leaves sometimes branched or even netted, 

 almost as in Dicotyledons. Flowers closely packed in a dense 

 spike, called a spadix, with a leaf-like or coloured bract at the 

 base, called a spatha. The stamens and ovaries either in dif- 

 ferent parts of the spike or mixed together, without any peri- 

 anth, or separated by small scales, which rarely form a small, 

 regular perianth. Ovary with 1 or several cells, each with 1 

 or more ovules. Eruit a berry. Seeds with or rarely without 

 albumen. 



A considerable family, chiefly from the tropical and warmer parts of the 

 globe, where many acquire a considerable size, or chmb up the stems of 

 trees. The large spatha and broad leaves are at once characteristic of the 

 majority of species ; a few however come near to the Bulrushes in habit, 

 but are always distinguished by their succulent fruit, and in most cases by 

 the seeds, or at least the ovules, not sohtary. 



Leaves broad. Spatha large 1. Aeum. 



Leaves and spatha long and linear. Plant reed-like 2. Aoobtjs. 



