Me REVUE BRYOLOGIQUE 
the distribution of the species. Æypnum lycopodioides and H. 
Sendineri grow together in the following localities, and in all of 
them 7. Wilsoni also occurs : — Strensall Common, Skipwith 
Common, St Annes-on-sea, Birkdale, Formby, Ainsdale, and for- 
 merly Southport. Æypnum lycopodioides occurs alone at Semer- 
Water and Pilmoor in Yorkshire, in Durham, and hitherto no form 
Of A. Wilsoni has appeared on record for these localities. Hypnum 
Sendtneri similarly occurs alone at Naburn, Askam Bog, Coatham 
_marshes, Burscongh and Rainford, and in none of these localities 
does it yield forms resembling 4. Wilsoni. 
[must admit however that in the Census Catalogue of British 
_ mosses /7. Wilsoni is recorded from certain counties in which 
_neither Æ. lycopodioides nor H. Sendineri are shown to oceur. 
_ Its appearance therein alone may be .accounted for in three 
Ways (1). By its having been accidentally introduced (2). By the 
existence of the two parent species not having been detected 
through imperfect exploration of the district and (3), by their 
disappearance prior to the locality being examined by a :ompetent 
botanist, 1 admit the weakness of the last suggestion, as in all ‘ 
probability circumstances leading to the extinction of the two 
parents would affect the hybrid in a similar manner. 
HYPNUM LYcoPODIOIDES Schwaeg. — In the North of England this 
species is a remarkably constant one, showing little variability in 
its essential characters. It is very abundant in some of its loca- 
lities, varying with the local conditions from two to 18 inches in 
length, and is sometimes slender, sometimes turgid and obese. 
Nevertheless it is always easily distinguished from any of its 
congeners without reference to the microscope, and could not 
possibly, under any cireumstances be mistaken for any of them. 
Some rare forms from Siberia. however, shows remarkable diver- 
_gence from the type. 
HYPNUM cariLuiroLIUuM Warnst. —- Herr Münkmeyer suggests the 
dissolution of this species, and distribution of its varieties under 
the other Harpidia which they most nearly approach. He regards 
it as analogous to the forms of Amblystegium filicinum and A. irri- 
guum With excurrent nerves. Whilst Strongly inclined to agree 
with Herr Münkmeyer, in they absence of practical experience of 
these plants except as herbarium specimens, I feel compelled to 
follow Renauld, Warnstorf and Dixon in keeping them distinct. 
It is also to be observed that Braithwaile maintains the specific 
rank of Amblystegium fallax Milde (= Hiypnum filicinum var. “à 
-Vallis clausea.) | 
The following list of the Harpidia adunca is the outcome of an 
