132 Rhodora [June 



mentions the tall freely-branching habit, the blunt or retuse leaves, 

 the ample clasping finely striate olive-green sheaths, the very short 

 (1 mm.) entire ligule, the long spike of 5-11 (usually 7-8) whorls, 

 which are equally distant or the lower farther spaced. AH of these 

 points would fit the American P. moniliformis described above, and, 

 in fact, in Kihlman's citation of stations, with the six in Finland and 

 Sweden, is one in North America: Saskatchawan, Bourgeau, Palliser's 

 Expedition 1858, which he had seen in the Herbarium at St. Peters- 

 burg. The two sheets of this collection seen by the writer are tall 

 coarse, freely branching plants with six and seven whorls, but they are 

 very immature and show no sign of fruit. The American material 

 with fruit shows it to l)e but 3 mm. long and with the sessile stigma 

 borne near the ventral margin. On the other hand P. ragiiiatiix 

 Turcz. has the "fruit 3.2 3.5 mm. long and the stigma flattened, 

 almost median on the fruit." ] Bennett 2 says of it "beak very short, 

 central," and his plate 58 drawn from Swedish specimens shows 

 clearly this condition. It is because 1 of this fundamental difference 

 in the form of the fruit, the asymmetric position of the stigma, that I 

 have described the American V. moniliformis as a distinct species. 

 In recording /*. vaginatus from Great Britain Bennett 3 cites two Ameri- 

 can stations, Assiniboia, Macoun! Buffalo Lake; and Labrador, 

 Waitz! in herb. Boissier. The Buffalo Lake material, as cited above 

 is P. moniliformis and the Labrador material may well be the same. 



5. P. filiformis Pers., Syn. pi. i. 152 (1805). /'. 'marintu, var. (?) 

 occidental™ Robbins, King's Rep. 339 (1871). /\ filiformis, var. 

 occidentals (Robbins) Morong, Mem. Ton-. Hot. ("1. iii. No. 2, 51 

 (1893); Bennett, Ann. (onsen. .lard. Geneve i\, 102 (1905). P. 

 interior Rydb., Fl. Colorado, 13 (1906); /\ marintu L. ace. to some 

 authors, not L. herb. Kootstock creeping: stem usually short and 

 repeatedly branched near the base giving the plant a very bushy habit, 

 but in deep water the branching reduced and the stem elongated 

 up to 30 cm.: sheaths short, tightly clasping 1 he stem, not becom- 

 ing divergent, about as long as the scarious early deciduous ligule; 

 blades filiform, blunt, 5 12 cm. long, 0.25 0.5 mm. wide: peduncle ex- 

 ceeded by or overtopping the leaves: mature inflorescence elongate, 

 interrupted, 1.5 5 cm. long; verticels mostly remote, the tipper usu- 

 ally 3 12 mm. apart, the lower usually 0.7 2.5 cm. apart: fruit obo- 

 vate, 2 mm. long, 1.5 mm. wide; the stigma broad and sessile. — 

 Shallow pools, chiefly in calcareous areas in the boreal parts of 

 North America; also Eurasia, Africa and Australia. 



1 K i 1 1 1 1 1 1 ; i n . I. c. 



Baonetl in Fryer, PotamuKctons of I lie Hrilish Isles SS, Plate oS (1!)1.">). 

 • Bennett, Hull. Herb. Hoissier iii. 257 (1895), and Joum. Hoi.. XI. V. 172 (1907). 



