326 DR. HOOKER ON THE DISTRIBUTION OF ARCTIC PLANTS. 



according to the different views of botanists. Thus P. Valdlana, L., is the nivea var. y 

 of Torrey and Gray, and includes Jamesoniana, Grev. P. pulcheUa, Br., is a very arctic 

 form, and according to Brown is Greville's sericea, L., between which plant and nivea it 

 ap]iears quite intermediate ; all depends upon what arbitrary character is assumed to be 

 the diagnostic one. 



P. Keilhami, Sommf. Of this I know nothing ; Nyman doubtfully refers the Spitz- 

 bergen plant of this name to Brown's pidchella. P. frigida ? Grev., is referred here by 

 Brown, and by Torrey and Gray under Vahliana, L., /3, which is also the P. Groenlmidica, 

 Br., of the same authors. 



P. frigida, Vill. I am quite ptizzled with this. Arctic American and Greenland speci- 

 mens seem to connect P. minima, Hall. {Brauniana, Hoppe), glacialis, Hall., and nana, 

 Lehm. The United States plant, found only on the White Mountains (P. Robbinsiana, 

 Oakes), is referred to minima j3 by Torrey and Gray, and afterwards to frigida, Vill., by 

 Gray, who observes that the European minima is probably a variety. The Danish au- 

 thorities refer the Greenland and Labrador plant to P. emarginata, Pursh {nana, Lehm.), 

 whilst both Asa Gray and Durand refer it to frigida, VilL I cannot help suspecting 

 that p. elegans, C. & S., of Eastern Siljcria, is the same thing, and that all will be 

 found to inosculate with the varieties or forms of P. verna. I have confirmed Torrey 

 and Gray's conjecture regarding nana, Lehm., being the same with emarginata, Pursh. 



P. verna, L. Under this, as one collective species or group of subspecies and varieties, 

 I have introduced five North European arctic and alpine plants, whose forms inosculate 

 perplexingly. The typical P. verna is not Lapponian, according to Pries ; and none of its 

 included forms occur anywhere in N.E. America, except Labrador and Greenland (as- 

 suming that hljlora is distinct as a species). P. aurea, L., is distinguished by Koch by 

 its leaves silvery beneath ; the aurea of Smith he refers to aljjestrls. Hall. I find this 

 character to be very variable. P. crocea, Schl., is referred by Koch to a variety of alpestris ; 

 he has, however, a var. crocea of verna. P. maculata, Lehm., is, together with aurea 

 and crocea, referred to Salisburgensis by Torrey and Gray. — P. Salisburgensis, Hgenke, is 

 regarded by Koch as a synonym of al])estrls. Ruprecht, who observes that Salisburgensis 

 is found throughout the arctic Island of Kolgujew, says that it is the same with '2;erra«,L., 

 " genuina." P. alpestris, Hall. : this, which is a much larger-flowered plant than the 

 ordinary verna, and otherwise difi'erent in habit, is kept distinct by Pries. Koch also 

 distingxiishes it from verna by its habit and ovate stipules, and from aurea by the leaves 

 not silvery beneath. Bentham regards both aurea and alpestris as luxuriant forms of 

 verna. Watson suggests that the distribution of verna, alpestris, and Salisburgensis 

 should be treated in Great Britain as that of one plant. 



Pragaria vesca, L. I have adopted the conclusions of J. Gay (Ann. Sc. Nat. ser. 4. 

 vol. viii. p. 196) for the distribution of this plant, but very much suspect that it would 

 have been more consistent to have (for distributional purposes) included that of collina, 

 Ehr., canadensis, Mich., and Chilensis, Ehr., under it. 



Sanguisorba officinalis, L. The four species brought under this vary very much ; and I 

 douljt if the majority will ever rank above local or permanent varieties. S. officinalis itself is 



