JOSSELYN BOTANICAL SOCIETY 



7 



Key to the Hair-Cap Mosses of Maine. 



Prof. J. Franklin Collins. 



[Condensed from a lecture given before the Josselyn Botanical Soci- 

 ety of Maine, at the Portland meeting, Feb. 24, 1911.] 



Disregarding many of the more technical characters of the 

 genus Polytrichum (as interpreted by the older bryologists) 

 it may be recognized by the angled capsules, the densely 

 hairy calyptra, together with the many lamellae on the upper 

 surface of the leaf. This latter character can be seen only 

 with a higher magnification than that furnished by the ordi- 



nary pocket lens. 



i. Leaf margins serrate, not folded over the lamellae 2 



1. Leaf margins folded over the lamellae, no teeth visible 



at the margin 6 



2. Marginal cells of the lamellae in cross section higher 



than broad. Capsule broadest below the middle. 

 Rare. Polytrichum gracile Dicks. 



2. Marginal cells of the lamellae in cross section broader 



than high 3 



3. Marginal cells of the lamellae transversely oval or 

 elliptic. Capsule usually broadest at the mouth and 

 tapering towards the base. Common in woods, etc. 

 Polytrichum ohioense Ren. and Card. 



3. Marginal cells of the lamellae in cross section more or 



less crescent shaped 4 



4. Leafy plants (gametophytes) long, typically more 



than six inches (often very long), with more or less 

 shining leaf bases. Capsules large, nearly if not 

 quite a quarter of an inch long. Calyptra hairs 

 usually golden brown 5 



