60 



in the Arctic, so that we still know very 

 little about such important biological 

 aspects in arctic t\pes as perennation 

 and dispersal mechanisms, propagation 

 except in obvious ways, reaction to the 

 almost continuous summer illumina- 

 tion, and the maturation of fruits and 

 seeds. 



"Ilie apparent ^•outh of the plant 

 communities and of soil formation are 

 noticeable. Also it will be found that 

 the plant associations are often mixed 

 and jumbled in a complicated, puzzling 

 way. To what extent they are climax 

 tvpes is problematical, though such 

 mixtures are often loosely called "poly- 

 climax." For, unlike the situation in 

 regions of more genial climate, it is 

 evident that, at least in the high-arctic, 

 plants rarelv take sufficient hold of the 

 surface to control even the immediate 

 soil environment. Instead we have a 

 situation in which they live anywhere 

 they can, and the vegetation is very 

 largely an expression of habitat differ- 

 ences. 



Where the local changes are so end- 

 less and drastic as in the Arctic, with 

 its extreme microrelief and microcli- 

 matic aspects, the complications of 

 frost-heaving, snowdrift, and snowmelt 

 phenomena, and of a relatively small 

 or at best highly impotent plant life, 

 induce or anvhow allow almost endless 

 vegetational change from spot to spot. 

 Nevertheless, competition and strug- 

 gles for food and space undoubtedly 

 exist among arctic plants, and so do 

 some kinds of successional tendencies. 

 This last point should be emphasized 

 in view of the denial bv some enthusi- 

 asts, who apparently have not worked 

 in the real Arctic, that plant succession 

 occurs there. 



STUDIES ON CRYPTOGAMS 



Before we leave the realm of the 

 taxonomic and ecological, some analy- 

 sis should be attempted of the degree to 



PHYTOGEOCRAPIIY AND EXPLORATION 



which the various ervptogamic aspects 

 have been investigated. The bacterial 

 floras of the Arctic have been little 

 studied, and the same is unfortunately 

 true of the Fungi, in spite of their many 

 and diverse species. The Algae and the 

 Lichens, on the other hand, have been 

 quite extensively studied in Arctic re- 

 gions—especially the Lichens and the 

 microscopic freshwater Algae, such as 

 the Desmids and Diatoms, and the ma- 

 rine planktonic plants. Numerous pub- 

 lications are available on arctic Mosses 

 and Liverworts, and also on the few 

 arctic Ferns and other Pteridophyta, 

 but there is considerablv more to be 

 done. 



PHILOSOPHY OF DISCIPLINES 



At one time there was considerable 

 interest in Scandinavian centers and 

 particularly in Copenhagen, where 

 plant material from Greenland was 

 being studied, in the form and general 

 biological attributes of arctic plants. 

 This investigation might be expected 

 to increase as a fertile field of study, 

 particularly with regard to the question 

 of plant reactions to the harsh arctic 

 environment. Research in this field, 

 however, seems to have decreased or 

 rather to have had its place taken by 

 cytolog}-. Cytotaxonomic and genetical 

 studies of arctic plants, or of plants 

 which reach the Arctic, have recently 

 been appearing in a broadening stream. 

 These are indeed welcome but it is to 

 be wished there were more simple 

 transplant experiments. Such are neces- 

 sary^ to determine whether specific in- 

 stances of the ven' numerous dwarf 

 and other plant forms that are found 

 in the Far North are genetic types 

 worthv of higher taxonomic rank, or 

 are merely ecological forms (ecads) 

 that result from the impress of the en- 

 vironment on the one generation. Cer- 

 tainly some of these modified types are 



