40 J. O. HAOSTROM, CRITICAL RESEARCHES ON THE POTAMOGETONS. 



P. drupaceus Lang, Fragmente etc. in Flora II, 1846, 476. — P. flabellatus Babing- 

 TOJT, Manual of Brit. Bot. ed. 3, 1851, 343. — P. vaginalis Fischer, Verzeichn. 

 Gef. pfl. Neuvorpomm. 1861, 40. — P. filicaulis ScHUR, Enumeratio pi. transsilv. 

 1866, 633. — P. latifolius Morong, Najadaceae of N. Amer. 1893, 52, tab, 59. — 

 Figg. 15, 16, 17, 18. 



»P. pectinatum — — — Habitat in Europse fossis & paludibus* Linne 1. c. This 

 species is not mentioned in his travels nor does he record any Swedish station in 

 his Flora Suecica. It is therefore likely Linnb had not studied the species in nature 

 but had seen only herbarium samples fixed on a paper (»foliis — — — para]lelis»). 

 At any rate, he has had a fresh-water plant in view. 



P. marinus L., again, is the plant Linne on his Gothland travel observed in 

 brackish water outside the estuary of Gothum-rivulet. It is most completely described 

 of all Potamogeton-s^eoies. From the account of the journey we cite (p. 221): — 

 Gothum-aen — — — Orterna har pa orten voro besynnerligen kring Gothum-Elfven 



desse, Hedera — — — Pyrola — Anthericum — Linnsea; Nymphsea alba 



& lutea; Alisma; Chara caulibus aculeatis; Potamogeton pusillum fluitans Bocc. hvars 

 caulis var ramosissimus; foliis alternis, lineari-subulatis, angustissimis ; ad ramifica- 

 tiones vero caulis notatiis; stipulis latis, amplexicaulibus, e quarum dorso folia soli- 

 taria. And from Flora suecica ed. 2: — ■ Folia stipulis ipsis insident in hac specie, 

 nee stipulae distinctse in alls foliorum, uti reliquis. Consequently P. marinus is a 

 plant with abundant and prominent ramification, rich in stem-leaves that are acute 

 and endowed with prominent, amplexicaul, broad sheaths etc. which just coincides 

 with P. pectinatus but not with filiformis Pers. The fact that Linne has twice 

 described the same species is easily accounted for by the above said. E. Fries, 

 again, evidently thinks less of the description than of his gathering the P. filiformis 

 at the Linnean station for P. marinus: — locoque ab ipso accurate indicato hie, 

 et nullus alius similis, quotannis coUigitur (Summa Veg. p. 216). But, of course, 

 both the species have grown at the same place. 



P. striatus, to which P. australis Phil, might be a synonym, I consider to 

 be a variety of P. pectinatus. Neither the original description, nor descriptions given 

 by different authors after the original specimens, nor specimens from South America 

 examined by me seem to me to be specifically separated from P. pectinatus. The 

 fruit is not smaller than this species often has (microcarp forms). Leaves and sheaths 

 nearly coincide with »P. zosteraceus*. The broadest leaves certainly attain to a width 

 of 5 mm, but also European forms are met with reaching this measure. The ana- 

 tomy of the stem and leaves does not differ in any essential point. At all events, 

 it is sure that the Sprucean specimens (n. 5886) from the Ecuador Andes, in the 

 Natural History Museum of Stockholm (Riksmuseum) are nothing else than a form 

 of pectinatus. 



P. zosteraceus Fr. is still in 1907 by G. Fischer considered as a proper spe- 

 cies yet without any real motives for such a statement, nor could they ever be 

 presented. 



