Yorkshire Naturalists at Dent. 275 



The stems (at the apex of the wedge) are imbedded in coarse sand or 

 gravel, a few leaves occur on the more sheltered leeward side. The 

 weathering of the grits and the resultant sand movements appear to 

 prevent these areas from passing into extensive Rhacomitrium heaths 

 such as are found in the Lake District and in Scotland at similar altitudes, 

 but where the rocks are more durable. 



Flowering Plants.- — In addition to the plants common to the 



■district the following species were observed : — 



Geranium sylvaticum Allium vineale 



Salix herbacea Serratula tinctoria 



S. repens Carex rigida 



S. repens X auritu Convallaria majalis 

 Melica uniftora 



Ferns. — No fewer than 17 species of ferns were noted, and among 

 .them, 10 are worthy of mention, viz. : — 



Asplenium Ruta-muraria Lastraea montana 



A. viride L. Filix-mas var. Borreri 



Phyllitis Scolopendrium Polypodium Dryopteris 



Cystopteris fragilis P. Phegopteris 



Polystichum aculeatum Ophioglossum vulgatum 



Mosses. — Mr. Chris. A. Cheetham reports as follows : — The mosses 

 -of Great Blake Ghyll were well investigated and recorded by West in 

 the article cited in the circular. The striking features here are masses 

 of fruiting Hypnum commutatum Hedw. and Weisia rupestris CM. on 

 the limestones, fine Breutelia arcuata Schp. on the banks, Zygodon 

 ■mougeotii B. and S., varying in colour from pale brown to black below, 

 abundant further up the stream. In the water, Fontinalis aniipyretica l! 

 Hypnum ochraceum Turn, and Hyocomiiim flagellare B. and S. point to a 

 soft type of water. Other interesting species in this locality are Bar- 

 iramia iikyphylla Brid., Plagiobryum Zierii Lindb., Fissidens osmun- 

 ■ doides Hedw., Webera carnea Schp. c. fr., Mnium orihorrhynchum B. and S., 

 Encalypia ciliata Hoffm., Trichostomum. crispulum var. nigroviride 

 Braithw. and T. tortuosum var. fragilifolium Dixon. 



On the moor above are Polytrichum alpinum L., P. strictuni Banks, 

 Splachnum sphaericum Linn, fil., and Dicranodoniium longirostre var. 

 alpinum Schp. ; and on grit rocks near the springs at the head of the 

 stream Andreaea peirophila Ehrh. 



The mosses of the summit are few, but amongst them may be noted 

 Rhacomitrium heterostichum var. gracilescens B. and S. The much 

 coveted Aulacomriium turgidum Schwaeg. was not seen. 



Greensett crags face too much south and are not backed by high 

 ground to keep them wet, and proved uninteresting, no additional species 

 being found there. A fine ghyll commences at their north end and runs 

 down to Ribblehead and Chapel-de-dale, known as Force Ghyll ; this 

 is a good place and the best find of the excursion came from here, masses 

 ■of Bartramia Halleriana Hedw., 5 to 6 inches deep, and full of fruit ; 

 all the other mosses cited occur here, also Swartzia montana Lindb., 

 Blindia acuta B. and S., Pterygophyllum lucens Brid., and a very wide- 

 leaved form of Catharinea undulata W. and M. approaching C. crispa 

 James. 



Liverworts. — Mr. F. E. Milsom devoted his attention to the 

 Tiepatics of the district, and the following is his report : — 



As was to be expected from its situation. Dent proved to possess a 

 luxuriant hepatic flora, both on the open moorland and in the ghylls. 



On the sides of the Whernside, Leptoscyphits Taylori was traced up 

 as far as the 2,000 ft. line. Scapania dentata, with its handsome red 

 tinge, was abundant at the sides of the streams, being especially 

 prevalent near the summit, as was, of course, the common S. tmdulata. 



1921 Aug. 1 



