﻿492 



BOTANICAL GAZETTE 



and boulders to a depth of a meter or more. Exposure to light is 

 almost invariably extreme. Many of the gravel slopes and flats 

 come properly within the alpine meadow zone. Their vegetation 

 varies, of course, with the physical conditions under which it must 

 exist. The xerophytes grow always in isolated clumps or cushions; 

 the hydrophytes and mesophytes either in clumps or in fairly 

 extensive beds. The xerophytes most in evidence are: Erigeron 

 aureus, Antennaria lanata, Kalmia glauca, Arnica latijolia, Epi- 

 lobium angustifolium, Potentilla emarginata, Gentiana pro strata, 

 Dryas octopetala, D. Drummondii, Eriophorum polystichium, 

 Calamagrostis purpurascens, and Cryptogramma acrostichoides. 

 A number of these species are found also on the alpine desert. 

 This does not seem remarkable if one considers that, except for 

 increased cold and snow, the conditions under which the desert 

 plants exist are similar to those endured by the morainal xero- 

 phytes. 



The hydrophytes and hydromesophytes of the moraines are 

 numerous. They often form dense masses of vegetation along the 

 streams, especially on the more level flats. The species found, 

 named approximately in order of abundance, are as follows: 

 Trollius albiflorus, Claytonia lanceolata, C. parviflora, Rumexcrispus, 

 Oxyria digyna, C alt ha Macounii, Ranunculus Eschscholtzii, Petasites 

 frigida, Thalictrum occidentale, Parnassia fimbriata, Car ex nigricans, 

 Veronica Wormskjoldii, Castilleia miniata, Mimulus Lewisii, M. 

 caespitosus, Epilobium latifolium, Eriogynia pectinata, Leptarrhena 

 amplexijolia, Saxifraga Lyallii, S. rivularis, S. Nutkana, Tiarella 

 unifoliata, Aquilegia columbiana, A. flavescens, Silene acaulis, 

 Delphinium Menziesii, Anemone Drummondii, Parnassia parviflora, 

 Erythronium grandiflorum, Veronica americana, Pedicularis brac- 

 teosa, P. racemosa, Pinguicula vulgaris, Epilobium Hornemanni, 

 Erigeron jucundus, E. multiradiatus, E. salsuginosus, Comarum 

 palustre, Myosotis alpestris, Cynoglossum boreale, A pocynum andro- 

 saemifolium, Gentiana glauca, Gaultheria humifusa, Ligusticum 

 apiifolium, Val, >!>enaria hyper- 



borea, Senecio triangularis, Veratrum pedicularis, Rhododendron 

 albiflorus, Kalmia glauca, Elephantella groenlandica, Potentilla 

 emarginata, Prunella vulgaris, and Sibbaldia procumbens. 



