ii8 HOW TO KNOW THE MOSSES 



Plants growing on trees, often apple trees, and on rocks, 

 in small dark-green tufts; common; fruit common. 



Stems erect or ascending; short, usually about % inch 

 long; sometimes branched. 



ffl ^ Leaves about four or five times longer 



m^ /| than broadest part, sometimes too 

 K^ (y small to show outline; wide- spreading 



when moist; folded straight against stem 



a. 0. sordjdum. , , 



b. 0. anomalum. '^^en dry. 



c. Capsule of 0. Br aunii. Seta SO short that it rarely shows above 



enarge . leaves, except in one of the common 



rock-inhabiting species, O. anmnalum, when it is longer and 

 yellowish. 



Capsule erect, cylindrical or elliptical, with a tapering 

 neck, usually partly concealed by leaves; yellowish or red- 

 dish; mature in spring. 



Calyptra thinly covered with hairs. 



Operculum cone-shaped or short-beaked, not easily seen. 



Range, a cosmopolitan genus. 



The Orthotrichums will be found on trees or rocks in 

 the open as well as in the woods. The species are not 

 easily distinguished, but the generic characters, the 

 partially concealed capsule, except in 0. anomalum, 

 which grows on rocks, and the leaves folding straight 

 when dry, can be readily recognized. These mosses 

 most closely resemble the Ulotas (p. 120), but in Ulota 

 the leaves are strongly crisped when dry, except in U. 

 americana; the seta is longer so that the capsule is not 

 partly concealed by leaves, and the calyptra is con- 

 spicuously covered with hairs. The exceptions to the 

 characteristics given above, Orthotrichum anomalum 



