KUNGL. SV. VET. AKADEMIENS HANDLINQAR. BAND 55. N:0 5. 21 



brevibus, superne 10—15 mm, inferne 20 mm viddiusculis; pedunculus elongatus; 

 spica 2—4 (o)-verticillata parviflora. 



This form is extremely like P. pectmatus f. laxus Tis. It lias been collected 

 by D:r G. Tiselius at Stockholm 1896 (hb. Upsal.) and by him looked upon as a 

 »f. laxus i. 



2. f. gevaliensis n. f. — Longitudo foliorum et structura, color vaginarum, 

 stylus et stigma ut in P. filiformi; pedunculus autem brevior, spica 4 — 5-verticillata, 

 verticillis aproximatis ; sterilis. 



Habitat: Siveden, Gefle, in a ditch, 1818 (hb. Stockholm.), Gefle ballast-quay, 

 87, Zetterstrom (hb. Stockholm., Uppsal., Lund.). 



p. Intermedius Hagstr. 



3. f. Hartmanii n. f. — Gaulis 25 — 40 cm altus badeo-viridis, inferne cras- 

 siusculus. Folia ± angusta, 5 — 10 cm longa, vaginis brevibus, superioribus 15 — 20 

 mm, inferioribus 20—30 mm stepe crassiusculis ut in P. pectinato, fuscoviridibus 

 vel ± albido-marginatis prsesertim inferioribus. Spica vulgo 4— 5-verticillata, sem- 

 per sterilis. 



Distribution. Siveden, GestriJcland, Gefle, Orarne, 35, hb. Hn. (hb. Uppsal.), 

 Iggo, 97, Arnell (hb. Uppsal.). — Uppla7id, Lanna, Furusund, 96, Tiselius (hb. 

 Stockholm., Uppsal., Lund., Gotenb.) is n. 119 in Tisel., Pot. suec. exs. Ill; Norr- 

 telje, H. & D. Tiselius (hb. Uppsal.). n. 119 in d:o. — Sudermania, Osterhaninge 

 Galon, 87, Almquist (hb. Stockholm, the plant mentioned in Almqu. Bot. Not. 

 1889), 90, Ribbing (hb. Uppsal.), Jarna, Angsholmen, 81, 82, Sandbn (hb. Uppsal., 

 Lund.), Hallsfjarden, 93, Hagstrom (hb. Stockholm.). — Osfrogothia Jonsberg, in 

 several places (Olskar, Yttre Hogskar, Gubbholmen) coll. Elmquist, Stenhammar, 

 Hammarsten (Lono) (hb. Stockholm., Uppsal., Lund.). — Smoland, Lofta, Lerbo- 

 holms sufferance-wharf (hb. Stockholm.) on the same page as P. filif. and pectin., 

 evidently collected at the same time; Vastervik, 63, Holmstrom & Lyttkens (hb. 

 Lund.). — Oland, Bjornudden, 83, Nordstebt (hb. Lund.). — Gothland, Kapell- 

 hamn. — Denmark, Susa, 99, Baagoe (hb. Stockholm.), more slender and elongated 

 (river-form). 



4. f. abundans n. f. — Gaulis altus ramosior; folia longa, vaginis longis. 

 Distribution. Sweden, Ostrogothia, Jonsberg, Yttre Hogskar, 80, Elmquist 



(hb. Lund.). — Iceland, Laxa, Husavik, 99, Gudjonson (hb. Stockholm.); Myvatn, 

 76, Gronlund (hb. Uppsal.). On the same page a specimen of P. filif ormis f. 

 major Tis. and one specimen of P. pectinatus L., apparently collected at the same 

 place and parents to the hybrid plant. iV. Amer., Sault Ste Marie, Mich. 81, Hill 

 (hb. Haun,). 



V. Cuspidatus Hagstr. 



5. f. ysanensis n. f. — Gaulis tenuissimus, internodiis elongatis; folia angus- 

 tissima, pulchre cuspidata, vaginis fuscis, brevibus; stylus ut in P. pectinato. 



