242 ANNALS OF SCOTTISH NATURAL HISTORY 



cells at central base oblong, attached, ultimately hyaline, 

 .045-. 07 by .OO9-.OI3 mm., outwards smaller and from 

 4 to 6 perpendicular rows next margin quadrate, chloro- 

 phyllose, length .OI5-.O22 mm., upper cells large, hexa- 

 gonal, separate, .OI2-.OI8 mm. in longer diameter; capsule 

 on a short seta, emerging partly above leaves, pale then red, 

 8-ribbed, long and slender, contracting a little below open 

 mouth, then swelling gently and again contracting gradually 

 to seta which thickens upwards to where it joins capsule 

 and is there often slightly grooved ; teeth 8, pale, broad, 

 bigeminate, reflected when dry, cilia incurved slender and 

 short, lid shortly rostrate, calyptra greenish yellow, naked, 

 turning darker, smooth at first then closely grooved, regu- 

 larly and widely campanulate, covering capsule, apex sharply 

 acuminate, brown, occasionally showing one or two hairs. 



There is another Ortkotrichum similar to the preceding 

 as regards colour, areolation, size and place of growth, but 

 differing in several important particulars. The margins of 

 the leaves are strongly and closely revolute nearly through- 

 out, to the extent, a little below the middle, of a complete 

 spiral and a half or even a little more, viz., i|% The apex 

 is very irregular in outline, bluntish with nerve vanishing 

 below it, or apparently somewhat excurrent as a thickish 

 stump, giving the impression that propagula had formed and 

 fallen off or were about to form. Barren. 



This might meanwhile be named Orthotrichmn prcenu- 

 bilum. 



Plagiothecium rufovirescens. In large rather lax tufts of 

 a yellowish-green colour above, pale below with here and 

 there faint dashes of red, showing occasionally creeping 

 rhizomes in the subsoil whence arise numerous upright stems 

 of an inch or more in length, simple or emitting occasionally 

 short lateral branches, as well as rather numerous stolons 

 from the basal part of these stems, bearing slender, rather 

 longly acuminated leaves ; stem leaves arranged regularly, 

 not complanately, much less bifariously, undulating on margin 

 but nearly upright when dry, hollow and almost imbricated 

 when moist, and then presenting a considerable resemblance 

 to Hypnum purum (especially as the acumen is then some- 

 what recurved), broadly ovate, slightly acuminate, or rather, 



