Mo £& - 85e ANNÉE 1908 
REVUE BRYOLOGIQUE 
ParaissanT Tous Les Deux Mois 
Les manuscrits doivent être écrits en français, en latin ou en anglais 
Sommaire du n° 4 
Comments on the Harpidia adunca. A, WHELDON. — Brachymenium turgi- 
dum. DIxON. — Un nouveau Riella d'Algérie. TRABUT. — Addimenta ad 
floram bryologicam Hungariae. GYORFFY.— Bibliographie. — Nouvelles (1), 
— Clé analytique et figures des quarante sous-genres de l’ancien Lejeu- 
nea. LACOUTURE. 
“ 
Comments on the « Harpidia adunca », of Sanio. 
By J. À. WneLpow. F. L.S. 
The difficulty of definining the limits of species and varieties 
in this and other large groups of closely allied plants, has led to 
-(he recognition of a new grade in the scale of classification termed 
« subspecies ». With an increased number of observers and col- 
lectors, many new forms have been brought to light, tending to 
connect species formerly considered to be distinct and well defi . 
ned. Mons. Renauld has recently expressed the opinion that 
Hypnum aduncum, H. Sendtneri, H. Wilsoni, and Æ. hycopodioides 
should all be regarded as subspecies of ZZ. aduncum. It only now 
needs the discovery of a further connecting link or two, to eflect 
the union all the Harpidia into one arch-species! The term 
« species » is a purely empirical one, applied to a collection of 
individuals, and no valid reason could be urged against the for- 
mation of an aggregale under such a name as Æarpidium com- 
munis » or « Drepanocladus polymorphus! » In ïts favour it 
could be advanced that such a course would simplify the study of 
mosses for dilettante students ; against it might be alleged thatit : 
would retard our efforts to properly understand these plants, just 
as the convenient term « Rubus fruticosus » has done in the case 
of the Rubi, by causing many local Floras to be useless as sources 
of information for the batologist. 
Opinions differ as to the désirability of maintaining such a 
(1) Les nouvelles ne sont pas à la fin du numéro, mais à la page 100, 
parce que le dernier article a été imprimé en lithographie. 
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