CALLITRICHINE.&]. 



739 



evergreen leaves scarcely 2 lines long, 

 with their edges rolled back as in the 

 Heaths. Mowers sessile, very minute, 

 the stamens of the males protruding 

 from the perianth on slender filaments. 

 Fruit black, globular, about the size of 

 a pea. 



In mountain heaths and bogs, in Eu- 

 rope, Asia, and North America, very 

 abundant at high northern and Arctic 

 latitudes, and quite alpine in southern 

 Europe and central Asia. Common in 

 Scotland, in northern and western Eng- 

 land, and in Ireland, but now probably 

 extinct in southern England. Fl. spring. 



Fig. 892. 



LXVIII. THE CALLITHICHE FAMILY. CALLITEI- 

 CHINE^E. 



Aquatic, floating herbs, with opposite or whorled leaves, and 

 minute unisexual flowers in their axils. No perianth. Ovary and 

 fruit either 1-seeded, or 4-lobed with 1 seed in each lobe. 



Two genera, each of a single species, always placed next each other 

 though not usually united into one family. Allied in many respects 

 to the aquatic genera of the Oenothera family, they are sometimes 

 placed next to them ; but there is no perianth, and they are therefore 

 more frequently enumerated amongst anomalous MonoMamyds. 



I. CERATOPHYLL. CEKATOPHYLLTJM. 



Leaves whorled and dissected. Stamens several. Style 1. Ovary 

 and fruit entire, with a single seed. 



1. Common Ceratophyll. Ceratophyllum demersum, Linn. 



(Fig. 893.) 



(Eng. Bot. t. 947, and C. submersum, t. 679. Hornwort.) 



A glabrous perennial, the stems floating like those of a Myriophyll, 



t2 



