AULACOMNIUM. 281 



This very rare and pretty species has only been found with us on Whernside in 

 Yorkshire and on two or three Scotch mountains. It can hardly be confused with any 

 other moss except with the var. imbricatum of the following species ; from that it 

 differs in the broader, rounded, very obtuse, softer leaves, the almost entirely smooth 

 cells, and the absence of tomentum (on which account the stems readily fall apart). 



There is a slight inflation of the extreme basal angles of the leaf which produces 

 the effect of minute auricles. 



2. Aulacomniuin palustre Schwgr. (Mnium palustre L. ; 



Gymnocybe palustris Fries, Braithw. Br. M. Fl.) 



(Tab. XXXIX. E.). 



Very variable in size and habit ; stems robust, loosely or 

 densely tufted, "1-5 inches high, closely covered with brown 

 tomentum almost to apex ; sparingly branched, pale yellowish 

 green, rarely bright green ; leaves usually crowded, erecto- 

 patent, when dry more or less crisped and spirally flexuose, or 

 spirally appressed to stem or almost straight ; long (1-2 lines), 

 oblong-lanceolate or linear-lanceolate, shortly pointed or obtuse, 

 or gradually acuminate to a narrow point ; margin narrowly 

 revolute at base, and to a variable distance above, towards apex 

 finely but sharply denticulate or sinuose-crenulate ; nerve 

 vanishing below apex, very white and shining at back when dry ; 

 cells very small, irregularly rounded or angular, with thick often 

 sinuose walls and triangular-intercellular spaces, towards base 

 somewhat elongated, a few rows at the extreme base wider, some- 

 what inflated, more or less bi-stratose, brownish yellow ; all the 

 cells except the basal strongly but variably papillose on both 

 sides. Perichaetial bracts longer, narrower, more tapering, less 

 papillose. Seta 1-2 inches long ; capsule oblong or sub- 

 cylindrical, slightly gibbous or curved, cernuous, strongly sulcate ; 

 when dry contracted below the dilated mouth ; lid conical ; 

 peristome teeth long, acute ; processes of inner peristome about 

 as long, with 3-4 intermediate cilia of equal length. Dioicous. 

 Male flower terminal, discoid. Branches often producing flagelli- 

 form pseudopodia, naked or with a few scattered minute leaves, 

 and bearing at the apex a cluster of small gemmiform metamor- 

 phosed leaves. 



Var. /?. imbricatum B. & S. Leaves crowded, broader, 

 wider at apex and more obtuse, entire or almost so, hardly 

 twisted or quite straight and appressed when dry. 



Var. y. fasciculare B. & S. (Mnium fasciculare Brid.). 

 Stems much branched with short ramuli, leaves in interrupted 

 tufts. 



