342 IOWA ACADEMY OF' SCIENCE Vol.. XXVI, 1919 



Liip'DUiS litloralis. — This species often occurs with Jiinciis Icscitrii. 

 It is remarkable among Lupines for its prostrate habit. Nowhere 

 very abundant. 



Plaiilcujo iiiariliiniis. — This form is more tolerant of salt water 

 than any other land plant occurring in this section. Its favorite 

 liabitat is in clefts of the exposed faces of shore cliffs and rocky 

 islets where it often grows so low down that it must frequently be 

 submerged by the waves in winter. 



Poa iiMcrautha. — Plentiful in a few places. One of the most 

 effectual retainers of the beach sand where it occurs in sufficient 

 abundance. 



The association of plants we have been considering passes more 

 or less gradually into one much less subject to the influence of salt 

 water, though doubtless more or less affected by the fine salt mist 

 blown shoreward in windy weather. The area occupied by this 

 group is for the miSst part fully exposed to the wind, which is con- 

 sequently a most important factor in determining the character of 

 the vegetation. This is of course particularly true of the shrubs and 

 such dwarfed trees as are here capable of maintaining an existence. 

 The territory occupied by this association is a narrow strip of land 

 beginning just l)ack of the edge of the shore liluff'. or of the beach, 

 as the case may be,, and extending inland in some cases for several 

 lumdred yards, usually nnich less, according to the contour of the 

 land. Tlic area includes many seaward slopes, some moderately 

 level land, occasional sand dunes that have become more or less fixed 

 by vegetation, and a few small sphagnum bogs. The following 

 species occur here: 



Achillea millefolium Castilleja dixonii 



Aira caryophyllea Centaurium umbellatum 



Agospi-is apargioides Cerastlinn vulgatum 



Agrostis alba Chrysanthemum leucanthemum var. 



A. exarata piniiatifidum 



A. hyemalis Cirsium edule 



A. hyemalis var. geminata C. lanceolatum 



Alchemilla occidentalis Cornus canadensis 



Anaphalis margaritacea var. oc- Crepis capillaris 



cidentalis Peschampsia cs'spitosa 



Anemone oregana Dipsacus sylvestris 



Arctostaphylos tomentosa Disporum smithii 



A. uva-ui-si Epilobium angustifolium 



Aster douglasii E. glandulosum var. adenocaulon 



Bellis pevennis Erigeron canadensis 



Herberis aquifolium Festuca rubra 



Brassica campestris Fragaria chiloensis 



Bromus hordaceus Caultheria shallon 



B. marginatus Gentiana sceptrum 

 Calamagrostis aleutica Geraniun molle 

 Carox pansa Gnaphalium chilense 



