172 THE JOURNAL OF BOTANY 



a few minute lichens develope. On a few pebbles brought home 

 for examination we found Acarospora pruinosa Jatta f. nuda Nyl. 

 ex Lamy., A. sniaragdula Ach., and Bhizocarpon confervoides DC. 

 f . fuscescens Leight and f . dispersa Leight. We did not observe 

 at any of the points visited a fringing zone of Agropyron junceuni, 

 such as may be seen between Ainsdale and Birkdale, but the 

 species occurs sparingly on the coast. 



II. The Marram Association. — The dunes rise rather abruptly 

 from the strand, in some parts in a continuous slope, in others 

 with a low steep scarp. In the latter case the freely exposed 

 roots of Marram grass show that erosion by tide or wind has 

 taken place. This grass is the dominant plant, and the slightly 

 undulating dunes it forms are neither as lofty nor as much cut 

 into hills and valleys as those of the mainland. After reaching 

 their maximum height, which is low as compared with the dunes 

 between Formby and Southport, they fall in a gentle slope towards 

 the land, forming a depression or shallow valley, which roughly 

 and with some interruptions follows the contour of the coast-line. 

 There are a few deeper hollows in which water probably stands 

 for a short time in wet seasons, but there are no permanently wet 

 "slacks." In these hollows a number of mosses and lichens 

 carpet the ground, but none of them are of a distinctly hydro- 

 philous type. 



The following species of this association were recognizable at 

 this early season of the year : — 



Ammophila arenaria Link, dominant. 

 Agropyron junceum Beauv. Taraxacum officinale Weber. 



Festuca rubra (aggr.). T. ohliquum Dahlst. 



Senecio vulgaris L. Carex arenaria. 



The above plants are the first to appear ; further from the littoral 

 zone they all still persist, with the addition of the following : — 

 Arenaria serpyllifoUa L. var. Valerianella olitoria Poll. 



macrocarpa Lloyd. Galiiim verum L. var. viariti- 



Cerastium tetandrum Curt. mum DC. 



C. semidecandrum L. Polygomim Itaii Bab. 



Erodium maritimum L'Herit. Phleum arenariiim L. 

 E. cicutarium var. glutinosum Aira caryoph^jllea L. 



Clav. Bromus hordeaceiis var. lepto- 



Eryngium maritimum L. stachys Beck. 



A single lichen was noted on dead stools of Marram grass, viz. 

 Cladonia fimbriata Fr. f. exilis (Ach.). 



III. The Marram loith Bracken Association. — In the lower 

 part of the main depression, Pteris aquilina begins to appear 

 amongst the Marram grass, and soon forms a well-marked zone, 

 sharing the ground with the grass, and in places becoming the 

 dominant species. Here many of the plants mentioned in the 

 preceding group continue to flourish. Lichens and mosses carpet 

 the ground in profusion, thriving where the sand is enriched in 

 humus by the decay of the more luxuriant vegetation. Cladonia 

 alcicornis forms light-coloured patches, and together with other 



