1923. Megaw. — A Plea for Moss Study. 115 



" Key to the Harpidroid Hypna," reprinted from the 

 1921-2 numbers of " The Naturahst." Harpidia are 

 extremely variable in form and colour and perhaps in 

 no other group is there such warrantable scope for varietal 

 differentiation. Even in pre-Wheldon namings we have, 

 in the " Census Catalogue of British Mosses " for example, 

 under Hypnum aduncum Hedw., a list of varieties reaching 

 to 77. The type and var. fS each claim one Irish district ; 

 8 has nine Irish districts to its credit ; and in August, 

 1920, I gathered var. 77 near Groomsport, in Co. Down. 



There is much valuable work to be done in the field 

 of Irish bryology, and the new Society together with recent 

 additional literature make the present a suitable time to 

 appeal for recruits. The study of Mosses has not been 

 popularised to any great extent. It is comparatively easy 

 to excite interest in Flowering Plants and Ferns, but the 

 reasons often advanced for shunning bryology are more 

 apparent than real. The thought of the microscope perhaps 

 acts as a chief deterrent. The microscopic work required 

 is really very elementary, if undue " splitting " be avoided. 

 After *a little experience, many Mosses, once determined, 

 can be named in the field with or wdthout the aid of a 

 hand lens. The botanist who includes Mosses in his scope 

 has this advantage, that he may continue his field work 

 throughout the year. Examination of specimens may be 

 made even long after the date of collecting, as Mosses 

 well dried may be preserved for many years without 

 detriment. It is to be hoped that this fascinating branch 

 of study will not be neglected by the younger generation 

 of Irish botanists. 



Belfast. 



