MOSSES WITH A HAND-LENS 



57 



ing the lid from a ripe capsule with dissecting needles and ex- 

 amining with a high power lens. There are other species with 

 this peculiarity, but they are rare or local. 



G. PENNSYLVANIA Schwaegr., the Pennsylvania Grimmia, 



seems to be our most common 

 species next to apocarpa, but 

 in the northern portion of our 

 range it seems seldom to fruit 

 and is apparently little col- 

 lected. It is a large coarse 

 dark green moss from l /2 inch 

 to i inch high, slightly hoary 

 at the ends of the stems; 

 leaves lanceolate, appearing 

 very dark and opaque in the 

 upper part, margin strongly 

 recurved, hair-point short and 

 rough, cells at extreme base 

 elongated-rectangular and hy- 

 aline or yellowish; next 

 above these the cells are short 

 rectangular, as shown in the 

 figure. The spores mature in 

 late autumn, but operculate 

 capsules may be found in 

 April. 



G. OLNEYI Sulliv., Ol- 

 ney's Grimmia, grows in 

 dark green tufts, blackish be- 

 low, more compact and finer 

 Pints'' nfturS grained than apocarpa; stems 

 12. Capsule and often nearly denuded of 

 leaves below, about I inch 

 high ; leaves lanceolate from an ovate base, the upper ending in a 

 long rough hyaline hair, margins not at all reftexed; capsule ex- 

 serted on a curved seta; operculum beaked ; spores maturing in 

 April. On rocks, not rare in the lowlands of the central portion 



PLATE; XIII. Grimmia apocarpa (From Bry. Bur.), 

 i, 2, 3 and 4. Plants natural size. Fig. 60. Apex of upper leaf. Fig. 

 1 8. Operculum with the attached columella. The other figures are self- 

 explanatory. 



Leaf apex 



