green. Whorls of S-^IQ short branchlets, each of 7 joints with 

 6 brads at each joining. Nuoule? 'solitary :with 13 striae' ftndra 

 raominent crown.— Stagnant brackish pools;: .' Burdoch: Pool, 

 lialidouth; CornwtOl. Rei>. W. L. P. Oarnons. A. VIII. ' E. 1. 



*** .Stem qoated with)imce as many tuheei,as.,tlwreare,,hirfinelvkt^ 



\ill ffffih whorl, tho^e, opposite to ilifi branchlets ihegirmg, spinm 



, , , , or tubercles, the otifefs npt . , ; ; ■ ' ' ' i . , , i : 



13;'' C. vulgaris (L. ?) ; monoecious, st^ I'omjh finely striate 

 brittle, upper part of the branchlets without external 'tubes, 

 bracts only on the inner side of the branchlets, four long, two 2 — 4 

 times as long as the nucules, two equalling them. — E. B. 336. 

 C.fcetida A.Br., Atl. Fl. Par. 37. — Diffuse, usually incrusted. 

 The spinous or tubercular (primary) cortical tubes less prominent 

 than the secondary ones, collapsing when dry so as to place the 

 spines in furrows. Nucules with 13 strise and a short crown, 

 with the globule. — ^Ditches and streams. A. VI. — ^VIII. E. S. I. 



14. C. his'pida (L.) ; monoecious, si. thickened upwards spirally 

 furrowed rough brittle with setaceous spines, branchlets long, 

 bracts whorled (inner ones longer), nucules ovate shorter than the 

 bracts solitary with a globule.— -E. JB. 436. Atl. Fl. Par. 38 B. 

 — Opaque, greenish white, usually incrusted. St. covered with 

 minute tubercles ; spines very many, sometimes few, upon the 

 (i^p^resa^d TOimary tubes. Branches, lopg, acuminate, of 7 joints, 

 with (4—5 short bracts at each joining. — Ditches and pits. A. 



, '! .: ";V .-••;.„., i. 



15. C. tomentdsa (Lu); dicecioua-(?), stJhickened upwards spi- 

 rally sulcate rough brittle with scattered blunt iaJercies, branch- 

 lets incurved, bracts unilateral ovate-oblong mucronate-acute, 

 nucule shorter than the bract on each side of it longer than the 

 three in front. — C latifolia Willd. Hook. Icon. 532. — Opaque, 

 whitish green. St. with minute, distant, rather whorled, short, 

 blunt tubercles on the prominent primary tubes. — ^Belvidere 

 Lake, Westmeath, Ireland. A. VII. ? I. 



**** Stem coated imth 3 times as many tubes as there are branch- 

 lets in each whorl, two secondary between each pair of primary 

 tubes on ivhich latter alone the spines or tubercles are placed. 



16. C. as'pera (W.); dioecious, st. finely striate smooi^Jlexibh 

 with setaceous patent spines, branchlets short, bracts whorled 

 slender (2 inner longer), nucules narrowly oblong shorter than 

 the braotfl. — E. B. 8. 2738. — ^Not opaque, pale green. St. densely 

 crowded; spines scattered, often very short, or irregularly 

 whorled. Branchlets 6 — 9 in a whorl, of 7 joints, 4 — 5 bracts 

 at each joining. Nucules solitary, stride 12 or 13, crown pro- 

 minent. — -Stagnant water. A. VIII. E. I. 



