THE NOMENCLATURE OF POTAMOGETONS. 301 



of fruit remind one at first glance of those of P. Drummondii 

 Bentharo. 4 



P. Oakesianus Bobbins in Gray's ' Manual of North United 

 States,' ed. 5, p. 485 (1808). — I believe this to be the P. Nuttalii 

 Cham, et Schl. (in 'Linnea,' ii. p. 226, 1827), and the P. Purshii 

 (name only) of Tuckerman in ' Silliman's Journal,' 1818, p. 228. 



P. alpixus Balb. x pensvlvanicus Cham. — A plant sent by the 

 Rev. T. Morong from " Lake Champlin, at Ftriisburgh, Vermont, 

 U. S. Coll. C. E. Faxon, 18-8-82, supposed to be a form of P. 

 rufescens Schrad." I would suggest this may be an hybrid. Mr. 

 Fryer has remarked, " Why not P. Grijfiihii? " and I must allow 

 the likeness to that plant is remarkable. Still I cannot certainly 

 place it there ; and I make the above suggestion as I am not able 

 to place it elsewhere. Perhaps American botanists who may have 

 the opportunity will study it growing. 



P. ambyllphyllus Beck, and P. vertictllatus Lesquereux, two 

 fossil " species," had better be re-named, as bearing names applied 

 to recent plants. 



P. filiformis Nolte, Nov. Fl. Holsat. (1826). — It is not easy to 

 decide what name this plant ought to bear. The following have 

 been referred to it : — 



P. pusillus fiuitans Bocc. Ic. et Descrip. Bar. Sic, &c, p. 42, 

 t. 20, fig. 5 (1674), fide Fries. 



P. marinus L. Sp. PI. ed. 1, p. 127 (1753), ex Auct. Suec. non 

 Herb ! 



P. setaceum Schum. En. PI. Saell. 1, No. 170 (1801) ! 



I'.filiformis'Persoon, Syn. PI. 1, No. 16, p. 152 (1805), sec. Lange. 



P. capillaceum Morck in Herb. Mus. Brit. (1821) ! 



P. fascicul atus Wolf. ap. Boem. et Sch. Mant. 3, p. 365 ! (1827). 



P. marinus All. ap. Beich. Ic. Fl. Germ, et Helv. vol. 7 (1844). 



P. pectiuatus subs-p.fi/ifunnis Pers. (sp.), Hooker, Stud. Fl. Brit. 

 Is. ed. 2, p. 397 (1878) ! 



P. filiformis var. ? niscutiformis Beich. in Herb. Mus. Brit. ! 



P. Bocconi Linn, in ind. It. Gottl. p. 221, fide Fries. 



Is there any specimen of Boccone's plant at Vienna, or else- 

 where ? There is none in a collection of Boccone's at Paris (cfr. 

 E. Bonnet, Bull. Soc. Bot. Frauce, xxx. 213). If such a specimen 

 exists, and it should prove to be filiformis, I see no other course 

 than to adopt marinus L. as its name. Chamisso (Lmnaea, ii. 174) 

 says of Boccone's drawing, " mala icon" ; doubtless, if it refers to 

 pusillus, it is so : but one cannot avoid the impression that it really 

 represents a small state of filiformis — like fasciculatus Wolfgang. 

 Nolte says that his filiformis differs greatly from P. marinus, but no 

 doubt he was here referring to Hartmau's marinus, i. e., !'. zostera- 

 ceus Fries, as I possess specimens of his own gathering and naming, 

 which are clearly what we mean by P. filiformis. Gussonc, Fl. Sic. 

 Synp. 1, p. 208 (1842), refers Boccone's drawing to /'. trichoides 

 Chain., but if this correctly represents an actual specimen, that 

 seems impossible. There is no specimen in the Linuean Herbarium 

 that can be referred certainly to filiformis. At present it seems safer 

 to use filiformis of Nolte as the name, as this is certain, definite, 



