NOTES ON BEITISH POTAMOGETOXS 19 



Hagstrom says: " Such varieties as Trimmeri Casp. and ccrpillaris 

 Fischer, recorded as three-nerved and by this fact separated from the 

 main form are probably bastards." I do not know Fischer's j^lant, but 

 Trimmeri (our trichoides) is certainly not a bastard ; curiously enough 

 he quotes a Norwich specimen from Babington under his triclioides. 

 Caspary separated it from the type because that is figured with 

 one-tuberculed fruit and one-veined leaves, and this is the case in 

 the t}73e-specimens in the Berlin herbarium. Our plant fruits very 

 fi'eely in ISToi-folk. 



*P. FEANCONiciJS Fischer (P. pusillus x triclioides) f. aspicosiis 

 Hagstr. (p. 126). Hedge Court Mill Pond, Surrey, Beehy, teste 

 Hagstrom ; Ewood Pond, Surrey, Stralcer. 



The author refers to this specimens from " Glastonby [Glaston- 

 bury], Somerset, Murrey [Murray]." On receipt of specimens from 

 the late P. P. Murray 1 wrote : " I should call this pusillus var. 

 yseudotrichoides^'' and I still maintain this name, as the plant fruits 

 freely. Mr. Marshall notes " no triclioides in Somerset." 



P. PECTiNATTis L. (p. 39). Sweden to S. Lapland ; Norway to 

 Finmark ; Finland to 66° n. lat. {Rjelt) ; Scotland to Shetlands. 



The varieties of this species are treated very fully. They include 

 the following British forms : — 



Var. ungulatus Hagstr. f. suh-ceqiiabilis. River Leen, Notts 

 {Mitchell) ; Wallasey, Cheshire {Lomax). 



f. latiusculis Hagstr. Benwick, Camb. {Fryer). 



Var. diffusus Hagstr. f. laxus Hagstr. Hedge Court Mill Pond, 

 Surrey {Beehy) ; Chatteris, Cambs {Fryer) ; Stirling {Stirling ^ 

 Kidston) ; Outer Hebrides {Somerville) ; Orkney (Syme) ; Shetland 

 {Beehy) ; I. Man {Kermode) ; Castle Gregory, Co. Kerry {H. C, 

 Hart). 



The author refers P.Jlahellatus Bab. to P. interruptios Kit. and 

 does not consider it entitled to specific rank. 



P. VAGINA TUB Turcz (p. 32). 



He remarks : " Shetland, Beehy, see Journ. Bot. 1907, 192. I 

 am not fully convinced of the correctness of this statement." The 

 Shetland plant agrees with Swedish specimens accepted by Hagstrom ; 

 but I am not fully convinced that his Swedish specimens are correct : 

 I have two specimens of Turczaninow's plant from the original 

 locality : but this must be discussed elsewhere. 



P. FiLiFORMis Persoon (p. 14). Sweden very general and far 

 north ; Norway to 70° 51' n. lat. {Norman) ; Finland to 69° 40' 

 n. lat. {Wainio) ; Scotland to Shetlands {Beehy). 



The author uses the above name, not accepting P. nnarinus L. 

 With regard to the use of the latter the specimens so-named in the 

 Linnean herbarium 2,\:q pectinatusX In Rhodora (1916, p. 134) 

 Mr. H. St. John takes me to task for using marinus, as I had 

 previously used Jiliformis, and his arguments are to the purpose ; 

 he writes *' In just such cases as this we are authorized by the 

 International Pules for Botanical Nomenclature to cast aside 

 the name ' when it becomes a permanent source of confusion.' " 

 But if a specimen could be found of the plant of Boccone on which 

 Linnaeus based his marinus and it proved to be Jiliformis, then 

 mai'inus would stand ; meanwhile 1 am quite content to use Jiliformis. 



