CL. I.] MONANDRIA MONOGYNIA. 47 



* Opaque, and very brittle. 



1. C. vulgdris. Common Stouewort, or Water Horse-tail. Stem* 

 branched, obscurely striated, smooth, never entirely incrusted ; whorled 

 branches awl-shaped, fertile ones with numerous short bracteas, three or 



four of which are much longer than the germen. From six to ten or 



more inches in length : principal branches alternate : germen egg-shaped, 

 sessile, in the centre of the floral leaves: anther sessile, upon the base of 

 the germen. The whole plant green when fresh, usually studded with 

 whitish, calcareous particles, and extremely fetid ; when dry, hard and 

 brittle. Annual: flowers in July and August : grows in muddy ditches, 

 pools, and slow streams, entirely immersed : common. Etig. Bot. vol. v. 

 pi. 336. Eng. Fl. vol. i. p. 6. 5. 



2. C. Hedmgii. Hedwig's Water Horse-tail. Stems branched, elon- 

 gated, obscurely striated, smooth, sometimes partially incrusted ; whorled 

 branches awl-shaped, fertile ones with numerous short bracteas, three 



or four of which are shorter than the accompanying germen. 



Larger than the preceding, with more numerous fertile branches. 

 Annual : flowers in July and August : grows immersed in still pools ; 

 rare. Buxstead, Sussex ; near Croft, Yorkshire. Eng. Fl. vol. v. 

 part i. p. 246. 6. 



3. C. aspera. Rough Water Horse-tail. Stems slender, obscurely 

 striated, everywhere covered with small spreading spines ; whorled 

 branches awl-shaped, the fertile ones with numerous short bracteas, 



those accompanying the germen of uncertain length. Annual : flowers 



in June and July : grows in pools in peat bogs: rare. Orkney ; Prestwick 

 Carr, Northumberland, Durham. Eng. Fl. vol. v. part i. p. 246. 7. 



4. C. hupida. Prickly Water Horse-tail. Stems furrowed, covered 

 by a calcareous crust, and armed above with small deflected prickles ; 

 whorled branches awl-shaped, fertile ones with numerous bracteas, 



of which three or four are longer than the germen. Larger 



than the three preceding species. Annual : flowers in July and 

 August : grows immersed in pools in turfy places : common. Eng. 

 Bot. vol. vii. pi. 463. Eng. Fl. vol. i. p. 7. A small variety of this 

 plant, without prickles, is sometimes met with. Eng. Fl. vol. i. p. 7. 

 The above four species of Chara may with propriety be reduced to one, 

 C. vulgdris, of which the three others are probably mere varieties. 8. 



** Transparent and flexible. 



5. C. translucejis. Great transparent Water Horse-tail. Stems elon- 

 gated, glossy; branches of the whorls elongated, simple, cylindrical, 

 obtuse, those bearing flowers axillar, compound ; bracteas indistinct, or 



wanting. The largest, the brightest coloured, and most glossy of all 



the species here described. Annual : flowers in June and July : grows 

 in stagnant pools : rare in England and Ireland, more comir.ou in 

 Scotland. Eng. Bot. vol. xxvi. pi. 1855. Eng. Fl. vol. i. p. 8. 9. 



6. C. fltxitis. Smooth Water Horse-tail. Stems repeatedly forked ; 

 whorled branches generally simple, obtuse, those bearing flowers axillar, 



compound ; bracteas wanting, or very indistinct. Stems from one to 



two feet long, slender, green, not crusted: anthers sometimes solitary, 

 but generally accompanied with two germens, or with one only, at the 

 forks of the whorled branches. More slender than the last. All the 

 species in this section are probably varieties of the present one. Annual : 



