THE WATER- HORN WOKX AND THE CROWBERRY FAMILIES. 361 



nnd discolor. The common Box-tree or Buxus sempervirens, (E. B. xix. 1341.) 

 is an excellent example of the family in regard to its three-celled fruit and uni- 

 sexual flowers, which are produced copiously in early spring ; and no less so in 

 the strongly poisonous quality of the deep green and perennial foliage. The 

 perianth is single and tetramerous ; the male flower is four-stamened ; the seeds 

 are hlack and shining. The hox used for the edgings of flower-borders is a 

 dwarfed variety, never seen in blossom. 



CXIV.— THE WATER-HORNW0RT FAMILY. CeratophjllAcecE. 



A family consisting, so far as at present known, of half-a-dozen 

 insignificant aquatics, whicli live wholly submerged in the water. 

 They have a very wide distribution, being found in almost all parts of 

 the northern hemisphere, but are of no discovered use. Two species 

 are reputed wild in England ; one of which is found near Manchester, 

 and the other probably no more than a variety. The Manchester 

 plant, or common water-hornwort, is a glabrous perennial, with stems 

 that float like those of the water feather-weed (p. 284), and are 

 densely clothed with leaves whorled in the same manner ; but instead 

 of being pectinated, twice or thrice forked, the divisions 1 — 2 in. loug, 

 slender, cellular, and rigid. The minute green flowers are sessile in 

 the axils of the leaves, and consist only of a few bracts, the male ones 

 bearing twelve to twenty sessile anthers, the females a small and 

 simple ovary, containing a single seed. 



HABITATS AND LOCALITIES. 

 Common Water-Horn wort — {Ceratophyllum demersum.) 

 Stagnant waters, ditches, and fish-ponds. " Worsley, Mr. John 

 Martin." (B. G.) Probably not rare. Fl. summer, but very seldom. 



E. B. xiv. 047 ; Baxter, iv. 200. The other form of the plant, or C. suhmersum, 

 is figured in E. B. x. 670. * 



CXV.— THE CROWBERRY FAMILY. Empetracem. 



The Empetracea) are small, dry, heath-like and evergi-een shrubs, of 

 not more than five or six species altogether, and in technical character 

 not very difierent from the box-tree family. Only one of them is of 

 interest, and that not so much on account of its beauty, as from its 

 value upon the moors, where its fruit is of great service to grouse and 

 other mountain birds. The stems trail close upon the ground, forming 



