Bjj Thomas Bruges Flower, Esq. 347 



Locality, "Waste and cultivated land. A. Fl. August, September. 

 Area, 1. 2. 3. 4. 5. 



Frequei/llj/ distributed throxighout the County. Leaves stalked, 

 ovate or oblong, rather coarsely toothed, of a thin texture. Male 

 flowers clustered as in the perennial Mercury along slender 

 peduncles, nearly as long as the leaves. Female flowers either 

 sessile or shortly stalked, usually on separate plants. Whole 

 plant bright green. 



ORDER. CERATOPHYLLACE^. (GRAY.) 



Ceratophyllum, (Linn.) Hornwort. 



Linn. CI. xxi. Ord. vii. 



Name. From ceras, ceratos, a horn, and phyllon, a leaf; in 



allusion to the stiff divisions of the leaves and fruit, which latter 



has two spines near the base, terminated by the curved tubulate 



style ; hence, too, the English name Hornwort. 



1. C. demersum, (Linn.) common Hornwort; demersnm (Lat. 

 signifies sunken, and is applied in allusion to the stems which are 

 long, slender, and floating under water. Fngl. Bot. t. 947. 



Locality. In ponds, ditches, and slow streams. P. Fl. July, 

 August. Area, * * * 4. 5. 



North Division. 



4. Korth-ivest District, In the Wilts and Berks Canal at Melk- 

 sham, Chippenham, and Wootton Bassett. 



5. North- east District, In the canal between Swindon and 

 Cricklade. 



Stems long, slender, floating under water. Leaves more or less 

 densely whorled, their segments setaceous. Flowers small, sessile, 

 verticillated in the axils of the leaves. Fruit elliptical. I have 

 no note of the occurrence of this species in the south of the county, 

 where it can scarcely be absent. 



ORDER. CALLITRICHACEiE. (LINDL.) 

 Callitriche, (Linn.) Water Starwort. 

 Linn. CI. i. Ord. ii. 

 Name. From [callos), beauty, and (thrix), hair, in allusion to 

 its very fine leaves. 



