Contributions to the Morphology, Synonymy, and Geo- 

 graphical Distribution of Arctic Plants. 



By Theo. Holm, Clinton, Maryland, U.S.A. 



With six photographs and eighteen figures in the text drawn by the author. 



The present contribution is divided into four chapters: I, containing notes 

 on morphological characteristics and synonomy; II, giving the geographical 

 distribution; III, concluding remarks, and IV, the bibliography relative to the 

 distribution. 



The fact that the collection made by the expedition contains many interest- 

 ing species, together with the fact that they have been collected and prepared 

 with great skill and care, has enabled me to examine their various organs, 

 principally the vegetative ones, and I am therefore able to offer some descriptions 

 of ramification, reproduction, hibernation, etc., of which several points are 

 but little known from arctic plants. 



Having had the opportunity myself to see the arctic flora, (Nova Zembla 

 and Greenland), and moreover to compare this with the alpine flora (Rocky 

 mountains, Colorado), I naturally feel induced to treat both as far as the scope 

 of the subject will permit. Therefore, in the chapter dealing with the distribu- 

 tion, I have inserted several columns for alpine plants, although the arctic 

 distribution has been given the most extensively, because, in respect to geograph- 

 ical distribution, the arctic and alpine floras are so intimately connected with 

 each other that a discussion of either one alone would give very little information 

 about their history. 



Considering together the interesting chapters on geographical distribution 

 in Darwin's "Origin of Species" and Nathorst's "Polarforskningens Bidrag till 

 Forntidens Vaxtgeografi," we have a most valuable foundation for further studies 

 in this line, and quite especially with reference to the arctic flora. 



CHAPTER I. MORPHOLOGICAL CHARACTERISTICS AND SYN- 

 ONYMY. 



GRAMINEAE. 



The species collected belong to the following tribes: Phalarideae, Agros- 

 tideae, Aveneae, Festuceae, and Hordeae; of these the Festuceae are the best 

 represented. They all are perennial and, concerning the habit, the stoloniferous 

 type is somewhat more frequent than the caespitose one; widely creeping stolons 

 above ground are characteristic of Glyceria vilfoidea; subterranean ones of Poa 

 arctica, Arctagrostis, Dupontia, Festuca rubra var., Elymus, Arctophila, and 

 Alopecurus; in the last three genera the stolons attain quite a considerable 

 length and ramify freely. The culms are always simple and usually short, 

 especially so in Glyceria tenella and G. vilfoidea, while in Elymus, Arctophila, 

 Arctagrostis, and Dupontia, the height of the culm may reach forty cm. or even 

 a little more. The inflorescence is most often an open, lax-flowered panicle, 

 notably so in Arctophila, Dupontia, and Poa arctica; a contracted, spike-hke 

 inflorescence occurs in Trisetum, Alopecurus, and Calamagrostis; a spicate one in 

 Elymus, Agropyrum, and Hordeum. The flowering glume ' is more or less hairy 



'The old, well known term "flowering glume" has recently become substituted by'lemma" proposed 

 by Professor C. V. Piper (Science, N.S. vol. XXIII, 1906), and is introduced in various manuals. Not 

 speaking of the fact that "lemma" has been in use for several years before as an anatomical term, proposed 

 by Strasburger, it seems unwise to change the old term "flowering glume," since this glume (gluma florens) 

 as well as the ^pty glumes (glumae vacuae) are bracts of the same order, borne on the same rhachis, 

 whereas the "palea" is borne upon a rhacheola, developed from the axil of the flowering glume. More- 

 over, in speaking of "lemma" in plurals, it is absolutely incorrect, from a linguistic point of view, to write 

 "lemmias" instead of "lemmata." 



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