INTRODUCTION 



At the request of the late Mr. James M. Macoun, I undertook the study 

 of the fungi collected by the naturalists of the Southern Party of the Canadian 

 Arctic expedition. Mr. Frits Johansen had collected about thirty species, 

 storing the fleshy ones in alcohol and preserving the others dry. 



In addition to the examination of these I have been afforded the opportunity 

 to examine the collections of phanerogams for fungi that might be found in- 

 habiting them. This experience was interesting in several ways. I was surprised 

 at the relatively small number of "summer stages" of parasitic fungi. On an 

 equal number of affected flowering plants collected in the southern latitudes 

 of Canada there would be a large majority of examples of the stage of fungi 

 reproducing by conidia or "summer spores" of some kind. Most of the fungi 

 inhabiting the arctic plants were found only in the ascigerous or mature condition. 



Another unexpected difference appeared in the wider range of host plants 

 inhabited by the same fungus species. In the south, as a rule, one fungus at 

 a time inhabits one host plant; in the north, it was not uncommon to find 

 two or three micromycetes on the same individual host plant, especially on those 

 plants that grow in dense rosettes or in the pillar form. On the latter the leaves, 

 though winter-killed or dead, remain firmly attached to the plant for years and 

 doubtless afford it protection. Fungi thus have the opportunity to become 

 established on a plant in successive years. Parasitism does not seem to play 

 much part. There, as here, the mature stage of the fungus seems to be quite 

 saprophytic or, at worst, invading the tissue only when its vitality languishes. 

 At Mr. Macoun's suggestion I have m&de notes of the findings in the important 

 orders of the fungi listed in the available reports of the flora of American arctic 

 regions, other than the one explored by the Canadian expedition. For that 

 purpose the following reports were usedi^ 



Meddelelser om Groenland, Bind III, Copenhagen, 1880, containing 

 Oversigt ov Svampe by E. Rostrup, 1888, and Tillaeg, 1891, by the 

 same author. 



Meddelelser om Groenland, Bind XVIII, Copenhagen, 1896, containing 

 Oest Groenlands Svampe by E. Rostrup, 1894, and Champignons du 

 Groenland Oriental. 



Meddelelser om Groenland, Bind XXX, Copenhagen, 1907-1911, containing 

 Fungi Groenlandiae Orientalis in Expeditionibus 1898-1902. Determ, 

 E. Rostrup, 1904. 



Meddelelser om Groenland, Bind XLIII, Copenhagen, 1911-1917, con- 

 taining Fungi Terrestres north of 76° N. Lat. Determ. C. Ferdinandsen, 

 and Systematic List of Micromycetes, Determ. J. Lind. (The speci- 

 mens were collected 1906-1908). 



The Nares Expedition on the Alert and Discovery, 1875-76, containing 

 enumeration of the Fungi by Rev. M. J. Berkeley, published in the 

 Journal of the Linnean Society, 1878. 



Harriman Alaska Expedition, 1899, Vol. V, containing Cryptogamic Botany 

 of Alaska, by William Trelease, New York, 1904. 



1 In the Report of the Interaational Polar Expedition to Point Barrow, Alaska, Washington, 1885, p. 192, Prof. Asa 

 Gray, in a brief report on the Plants, states: "There was a quantity of fungi preserved in a jar of alcohol, but without 

 notes of color, habit, etc., so that the specific determination is in their present state impossible. The specimens, as far 

 as could be told, seemed to include two species of Agaricus and one of Russula." 



50278—1* 



