KUNGL. SV. VET. AKADEMIENS HANDLINGAR. BAND 55. N:0 5. 



25 



L. (probably to the Museum of St. Petersburg) and Macottn's Catalogue Canad. 

 Plants 1888 records it from Buffalo Lake, lat. 56°. It is thus testified, that P. va- 

 ginatus, or a form of it, occurs in Canada (see under P. vagin.). P. filiformis also 

 is growing there, and the Winipeg-plant really has much, that reminds of the two 

 species: stem rather thick but the ramification as in P. filiformis; leaves narrow, 

 blunt, greyish-green; sheaths short, 15—20 mm, but rather dark and of strong struc- 

 ture, ligules persistent, even in the basal sheaths; peduncle short (— 60 mm) as in P. 

 vaginatus with almost overtopping leaves; spike of 4 — 6 approximate verticils. This 

 form should be called f. brevipes n. f. : ped. brev. — Another form, coll. by Low at 

 Fort Chimo, Labrador (hb. Haun.), with very long leaves and peduncles, I would 

 name f. longipes n. f. : ped. longiss. 



P. pamiriciis Baagoe. 



Potamogetonacese from Asia-media in Vidensk. Medd. fra den 

 naturhist. Forening. Kjobenhavn 1903, 182. — Fig. 6. 



In his dissertation (p. 183) Baagoe has mixed up two different 

 species. The same is the case with his assigning of names in the Mu- 

 seums of Lund and Copenhagen. The plant, gathered by 0. Paulsen in 

 Pamir and named P. pamiricus is quite another than that collected by RoBO- 

 ROWSKY in Kuen-Luen. This one has been found to be a beautiful, distinct, 

 new species separated from P. pamiricus, which is very nearly allied to 

 P. filiformis and scarcely specifically separated from it. The description 

 of Baagoe meanwhile refers to Paulsen's plant from Pamir and 

 the name pamiricus consequently is to be kept for this form. A 

 plant from Thibet (hb. Lund, et Haun.), gathered by T. Thomson and 

 determined by Baagoe, pretty well corresponds to the description 

 except a couple of measure-notes. Stem about 0,5 m high, the basal ^'^b^;. „^/7"T 

 internodes also elongated (4 — 8 cm); leaves as to length and width, «pex, v- Lacunar 



T , walla and marginal 



apex and nervature like a broad-leaved P. filiformis (the Pamirplant, bundles visible. 

 too, seemed to me to have 3-nerved leaves, Baagoe's description: 

 3 — 5-nerved, counting also the longitudinal lacunar walls?). The sheaths of the Thom- 

 son plant are 10 — 25 mm in length, those of the Paulsen plant somewhat longer, 

 especially the basal ones. Peduncle 3— t4 cm, spike 3-verticilled, flovs^ering 10 — 20 mm 

 long. Ripe fruit not seen. 



A transverse section of the Thomson plant showed a central cylinder with one 

 wide air-channel, a w-endodermis and three to four cortical strands. Robokowsky's 

 plant will be described farther below. 



Distribution. Asia, Tibet occ, 12—15,000', T. Thomson (hb. Lund.). Baagoe 

 has given to the Mus. of Lund a »P. pamiricus->-> labelled: »Asien. Pamir. In stagnis 

 prope lacu Kara-Kul, 1890, Ove Paulsen*, yet evidently originating from another 

 place, 



K. Sv. Vet. Akad. Handl. Band 55. N:o 6. * 



