43° HYPNACE^. 



Hab. On the ground in stony places, by roadsides, etc. ; very rare. Near 

 Wells (Binstead). Fr. winter. 



This very distinct species has only been added to our moss-flora within the past 

 few years, by the Rev. C. H. Binstead. The short, rounded, flaccid leaves with 

 extremely large cells render it a very marked plant ; the cells in all the previously 

 described species of the genus being less than half the width, and often much 

 narrower. 



1 13. PLAGIOTHECIUM B. & S. 



Stems irregularly branched, not pinnate. Leaves (in all the 

 British species) complanate or secund and homomallous (only 

 slightly so in P. demissum) , ovate or oblong-lanceolate, often 

 inserted obliquely and asymmetrical, two-nerved or nerveless, 

 cells rhomboid-hexagonal or linear, usually very chlorophyllose. 

 Seta smooth. Capsule slender, oblong-cylindric, more or less 

 curved, smooth or striate; lid apiculate, acuminate, or shortly 

 rostrate, rarely obtusely conical. Peristome more or less perfect, 

 pale. 



This genus is for the most part a very natural one, the greater 

 number of species being very distinct in their flattened stems and 

 branches with complanate leaves ; there are, however, a number 

 of intermediate species, some of them between this genus and 

 Eurhynchium, which seem best placed here, as they come 

 very near some of the species whose position in the present 

 genus is undoubted. I have thought it best to place here the 

 species usually known as Rhynchostegium depressum and R. 

 demissum. The affinity of the former to Eurh. confertum is 

 undoubted, but it is also very near some of the species of 

 Plagiothecium in habit, etc., and the complanate, almost nerve- 

 less leaves give it a marked claim to be included here. In the 

 absence of marked structural characters in the fruit and in the 

 areolation, to separate the genera of Hypnaceae, the character 

 derived from the single nerve or otherwise would appear to be of 

 considerable importance, judging from its constancy in some of 

 the well-defined groups of Hypnum and in other genera of the 

 Pleurocarps ; I have therefore thought it the soundest method of 

 classification (and it is also by far the most convenient to 

 students) to include under Eurhynchium only those species with 

 a single nerve (usually correlated with non-complanate leaves), 

 and to unite with Plagiothecium the single-nerved or nerveless- 

 leaved species having the leaves complanate or more or less 

 secund and homomallous. The rostrate lid of the two species in 

 question is of course no objection to this arrangement, as in other 

 species of Plagiothecium it is quite as long. 



