8 ENGLISH BOTANY. 
S. affine comes very near to 8. simplex, and is often with difficulty 
distinguished from the floating state of the latter. The following 
differences are observable. In S. affine the sheaths of the stem- 
leaves are more inflated, the stigmas are more thickened and ligulate, 
shorter and more oblique than in S. simplex, and decidedly thicker 
than the style, the fruit is more attenuated at each end, having a longer 
stalk and a longer beak. In fruit the heads are more equally stalked, 
even the upper “having commonly a short peduncle. The male heads 
are smaller, from the ‘filaments being shorter, and the whole plant is 
of a deeper green, less inclining to yellow. 
Whether S. affine be really distinct from the S. natans of Fries. I 
am unable to say. Both Nyman, in the “ Sylloge Flore Europe,” 
and ©. J. Hartmann, in the ninth edition of the “ Handbuk i Skan- 
dinaviens Flora,” separate them, the latter giving as synonyms of 
S. natans, [ries, S. Friesii, Beurling (whose paper I “have been unable 
to see), and S$. longifolium, Turczaninow. ‘The principal points of 
difference seem to be the branched flower-stem and more numerous 
male heads of S. natans, /’ries, but the stem is certainly occasionally 
branched in S$. affine. 
Specimens of S. affine from Shetland in the herbarium of the late 
Dr. Fleming were labelled by Don “S. longifolium, Don,” but I am 
not aware that he ever gave a description of the species. 
Floating Bur-reed. 
French, Itubanier flottant. German, Kleinste Igelskolbe. 
SPECIES IV—-SPARGANIUM MINIMUM. [Frvs. 
Puatre MCCCXC. 
Reich. Ic. Fl. Germ. et Helv. Vol. IX. Tab. CCCXXIV. Fig. 749. ; 
Billt, Fi. Gall. et Germ. Exsicc. No. 853, { 
S. natans, Linn. Spec. Pl. p. 1378 (ex parte). Sm. Engl. Bot. ed. i. No. 273. Koc ; 
Syn. Fl. Germ. et Hely. ed. ii. p. 786. Crep. Man. FI. Belg. ed. ii. p. 310 (non 
Linn. Fl. Lapp.). Fries. 
Leaves linear, flaccid, always floating, none of them triangular “ 
the base. Stem-leaves with the sheaths short, not inflated. Flower 
ing-stem floating, slender, flaccid, simple, the apex rising out of th 
water only at the time of flowering. Flower-heads in a spike-lik 
raceme or spike. Female flower-heads 1 to 3, shortly stalked, termi 
nating the peduncles of the raceme, the upper one, or sometimes 
of them, sessile on the rachis itself. Male flower-head solitary, sessil 
on the extremity of the rachis. Stigma oblong-lanceolate. Frui 
subsessile, ovate-ovoid, with a shortly conical top, rather suddenl 
~acuminated into a short beak. Leaves olive-green, subpellucid. 
In ditches and small pools, principally in peaty soil. Rather scare 
