CAHEX 541 



by the Thames near Iffley, at Blewbury, &c. ; it has the habit of 

 pralixa, but the spikes are of a pale ferrugineous colour, and the lower 

 glumes are aristate ; a form which is rather frequent by the Abingdon 

 Canal comes between this and the type. 



Var. TROLixA, Hartm. Scand. iv. 302. C. prolixa, Fries, Nov. Mant. 

 iii. 228 ;i842). A plant from ditches and sides of the Thames near 

 Moulsford is best placed under this form. Near Newbury a robvist 

 form occurs, w^hich has much of the aspect of C. elafa ; it is four feet 

 high, with long stout spikes. This was distributed through the Bot. 

 Exch. Club for 1890, and considered by the Eev. E. F. Linton to be 

 C. acuta in the direction of prolixa. A plant much nearer prolixa occurred 

 near Binsey. 



Var. GRACiLESCENS, Almquist, occurs in marshes and by canals, &e., 

 but it appears to be united to the type by intermediate forms ; in its 

 more extreme form I have seen it near Marcham, near Abingdon, and 

 near Eadley. Specimens from Abingdon were distributed through 

 the Bot. Exch. Club, 1892, by the author. 



Var. viKims, Hartm. A form with shorter and paler glumes and 

 prominent yellowish green perigynia. I have seen it at Wytham, 

 Appleton, by the Abingdon Canal, by the Loddon, and at Moulsford. 

 Is it distinct from the var. chlorostachya, Reichb. Ic. Fl. Germ, et Helv. 

 viii. f. 585 ? A clo!>ely allied form to this is a phint with shorter 

 spikelets which occurs by the river ditches near Kennington ; it 

 agrees excellently with specimens IsiheUedvAr.Jliiviatilisin Fl. Ingricae 

 Exsicc, but I do not know whether it is identical with C. acuia, 

 var. Jluviatilis, Hn. Sw. Bot. 498, cited by N. J. Anderson in Cyperac. 

 Scand. 44 (1849% 



Var. ZYGOSTACHYA, Reich b. Ic. Fl. Germ, et Helv. viii. f. 585 d, is 

 a monstrous condition in which both male and female spikelets are 

 branched ; it occurred by the Abingdon Canal. A condition of the 

 plant in which the upper female spike has some male flowers at the 

 apex is not uncommon ; it is the var. Moencliiana, Wend. 



Var. NiGKESCEXs, Druce in Rep. of Bot. Exch. Club, 388, 1892, in 

 which both perigynia and glumes are of a uniformly purplish-brown 

 colour, is possibly only a melanic condition. Dr. Lange considered it 

 to be only a form. 



In by far the larger number of plants placed under C. acuta, which 

 occur in Berkshire, the glume will be found to have a large number of 

 narrow transparent lacunae. 



Var. IMPUNCTA, mihi, in which the lacunae are absent, I have noted 

 from Abingdon and Wytham. 



I find that Boott in his Illustrations of the Genus Carex alludes to the 

 presence of the lacunae in C. acuta. 



C. acuta is found in all the bordering counties. 



