182 



N. 1445, 1446. Pamir, prov. Wakhan (Ishkashim), in a pond by Rang. 



Alt. 2000». Oct. 1. 1898. 

 N. 1590. Pamir, in a spring by Tshatir Task. Alt. 4000". March U. 



1899. 



10. P. pamiricus n. sp. 



Caulis strictus teres, in latere folio verso planiusculus, simplex 

 vel subsiraplex, 1 m. longiis vel longior; internodia luteo-viridia, 

 inferiora brevia (2 cm.), superiora longiora (8 — 12 cm.). Inferiora 

 pars caulis vaginis aphj'llis interdum dissolutis instructa; folia rigida, 

 angustissime linearia, obtusa, 3 — 5 nervia, inferiora superioribus 

 12 — 20 cm. longis 1 — 3 mm. latis breviora. Nervus médius (in 

 siccis) latere inferiore elevatissimus. Axilli non ramiferi^). Vaginæ 

 magnæ, 2 — 3 cm. longae, 4 — 7 mm. latae, rigidæ, virides, multi- 

 nerviae, subinflatae, earum margines versus basin membranaceæ. 

 Ligulæ subpersistentes obtusæ, superiores saltem vaginis fere 

 dimidia parte breviores. Pedunculus spiciferus 3 — 4 cm. longus 

 rigido-erectus, crassitudine æqualis, foliis multo brevior, ex axillis 

 superioribus nascens, realiter terminalis sed ad latus inflexus ita 

 ut lateralis videtur. 



Spicae pauciflores intervallis brevibus inter glomerulus. Fructus 

 immaturus parvus, obliquo-ovatus, stjlo brevi, stigma obliquo- 

 discoidea. Khizomam non vidi. 



N. 644. Pamir, in a pond by the lake Kara Kul. Alt. 4000». July 1. 

 1898. 



Potamogeton pamiricus belongs to the group Coleogeton Kchb.. 

 and this group being divided in two well separated undergroups, 

 viz. pectinatus- and filiforviis group, it belongs to the latter; of 

 hitherto described Potamogeton-sçQç\Q& the following belong to 

 the same group: P. filifoi^mis Pers., P. juncifolius Kern., P. 

 vaginatus Turcz., P. amblyophyllus C. A. Mever, P. strictus Phil. 



') Only at the lowest axil of the two apparently opposite leaves at the 

 base of the peduncle grows a shoot, which apparently is a continua- 

 tion of the stem, so that the peduncle is apparently hiteral. 



