;40 Review of Hooker'' s Outlines 



pogon.^ Of the 762, found south of tlie circle, all but 150 have, 

 advanced beyond lat. 40° N., in some part of the world ; about. 

 50 of them are identified as natives of the mountainous regions of 

 the tropics, and 105 as inhabiting the south temperate zone.' 



" The proportion of species which have migrated southward in. 

 the Old and New World also bear a fair relation to the facilities, 

 for migration presented by the different continents." The tables 

 given to illustrate this " present in a very striking point of view, 

 the fact of the Scandinavian flora being the most widely distribu- 

 ted over the world. The Mediterranean, South African, Malayan, 

 Australian, and all the floras of the New World, have narrow; 

 ranges compared with the Scandinavian, and none of them form 

 a prominent feature in any other continent than their own. But 

 the Scandinavian not only girdles the globe in the arctic circle, 

 and dominates over all others in the north temperate zone of the 

 Old World, but intrudes conspicuously into every other temperate 

 flora, whether in the northern or southern hemisphere, or on the 

 Alps of tropical countries." * ^ * *' In one respect this migration 

 is most direct in the American meridian, where more arctic species 

 reach the highest southern latitudes. This I have accounted for 

 (Flora Antarctica, p. 230) by the continuous chain of the Andes 

 having favored their southern dispersion." 



' In presenting the actual number of arctic species, and in deli- 

 neating their geographical ranges, the question, what are to be 

 regarded as species, becomes all important. As to this, it does not 

 so much matter what scale is adopted, as to know clearly what 

 the adopted scale is. Here we are not left in doubt. Taking 

 European botanists by number, we are confident that nine out of 

 ten would have enlarged the list of 162 pha;nogamous arctic 

 species to 800 or more, and would not have recognized a goodly 

 number of the synonyms adduced, thereby considerably affecting 

 the assio-ned ranges, especially into temperate and austral latitudes. 

 In this regard we should side with Dr. Hooker on the whole, but 

 with difterences and with questionings — with halting steps follow- 



* ' Douglasia is mentioned in another place (p. 269) as an absolutely 

 peculiar arctic or arctic alpine genus of E. America. But we have con- 

 sidered this genus as identical with Gregoria, of Duby. It would ap- 

 pear as if these two genera were established in the same year, since Lin- 

 dley himself, in the Botanical Register, refers to Brande's Journal for 

 January, 1828, for his original article. But this article will be found in 

 the volume of that Journal for 1827 ; so that the name Douglasia is to 

 be adopted, if the genua is sufficiently distinct from ^ndrosacej 



