only slightly emarginate, narrowly scarious-margined above, slightly inflated at the sum- 

 mit, and furnished with a subulate incipient leaf, about 3 mm. long. The spike is gene- 

 rally 5-flowered, the lowest glume commonly 5-nerved, and the elongated leaf-like process 

 most frequently of a green colour. As to the anatomical structure of the culm, to which 

 Palla has attached some systematic importance, may be noted that the intervals be- 

 tween the vascular bundles are completely filled up with green cellular tissue, the cells 

 of which have quite the same form, thickness of the walls, and diameter as usual; air- 

 courses are here altogether wanting. The specimens collected thus seemed to agree 

 best with 1. austriacus (Palla) Aschers. et Graebn. Synops. Mitteleur. Fl. II (1913) 

 p. 300. As the plants are so young, I have not been able to express an opinion on 

 the structure of the bristles. 



The species is of rather common occurrence in the Altaian, above the tree limit, 

 in swampy fields, where collected by me, with young flowers, at the end of July. 



Distribution: The species is distributed over the greater part of Europe, Siberia, 

 northern Mongolia, Sakhalin, Japan, North America, Greenland. 



Scirpus alpinus Schleich. in Gaud. Fl. Helvetica I (1828) p. 108. 



subspec. oliganthus (C. A. Meyer). Isolepis oligantha C. A. Meyer, Cyper. Nov. no. 

 3 in Mem. Pres. Acad. St. Petersb. I; Turczan. Cat. Baical. no. 1198; Ledeb. Fl. Ross. IV, p. 

 255; KpBiji. $ji. Ajt. VI (1912) p. 1433. Isolepis elongantha C. A. Meyer, Ledeb. Fl. Alt. 

 I, p. 64. Scirpus Meyeri Trautv. PI. Sib. Bor. sub no. 368. Isolepis pumila Roem. et 

 Schult. Syst. Veget. II (1817) p. 106; Turczan. Fl. Baical.-Dahur. (1855, II) p. 316, no. 1212. 



This form, which I refer here, is especially distinguished by its slender, filiform 

 culms and leaves, and small, ovoid spikes. The rootstock is creeping. The culms are 

 densely cespitose, generally about 20 cm. high, surrounded at the base by brown, 

 lustreless, rather narrow sheaths, obtusely cut above. The upper sheath, or the two 

 upper ones, are of a green or pale green colour, slightly membranous, with an erect, 

 setaceous leaf, from 10 to 25 mm. long, with obtuse, frequently somewhat yellowish sum- 

 mits. The culms are of a fresh green colour, erect, rigid, but very fine and slender, 

 scarcely exceeding 0,5 mm. in diameter, furrowed, round and glabrous, or only near 

 the summit sometimes slightly triangular. The spike is terminal, very small, most 

 frequently 3-flowered, rarely 2-flowered, ovoid or broadly ovoid, from 2 to 3 mm. long, 

 and of a light yellowish brown colour. The glumes are broadly ovate, obtuse above, 

 scarious-margined, frequently with a greenish dorsal nerve. The two lower glumes are 

 generally destitute of flowers, and with a base more or less surrounding the spike, 

 commonly not larger than the upper scales, apparently even smaller, and reaching only 

 half up the spike. Sometimes the dorsal nerve of the lower glume is prolonged into a 

 short, thick foliaceous tip, of a yellowish colour, thickened and obtusely rounded at 

 the summit whereby recalling much the lower glumes in Scirpus caespitosus. 



This tip, however, is always very short, scarcely over 1 mm. long, and generally 

 reaching only to half the height of the spike, never to the summit of the spike or exceed- 



173 



