ORTIIOTRICHACEAE 1 19 



Hedw. and Ulota americana, both grow on rocks and 

 closely resemble each other, as in both species the cap- 

 sule is raised above the leaves, and the leaves are not 

 crisped when dry. If the plants are not fruited, the 

 beginner will not be able to identify them, but if the 

 fruit can be found there is one character that differs 

 slightly. In the Orthotrichum, when the capsule is dry 

 and empt}^ it suddenly tapers at the base, while in the 

 Ulota it tapers more gradually. The Ulota will proba- 

 bly be more frequently collected. 



See also Andreaea (p. 75), Grimmia (p. iii), and 

 Drummondia (p. 116). 



Orthotrichum Braunii Br>^ol. Eur. (0. strangiilatum 

 Sull.) is a fairly common species and can be easily recog- 

 nized when fruited, by the capsule greatly contracted 

 below the mouth w^hen dry and empty, so that it re- 

 sembles a vase in outline. The other species have the 

 capsule only slightly or not at all contracted. 



23. ULOTA Mohr (U-lo-ta) 



A genus containing many species, four of w^hich can 

 be found in our range. The name is derived from the 

 Greek for "something curled," referring to the leaves 

 curled or crisped when dry. 



rJants growing on trees and on rocks, usually forming 

 small rounded cushions; yellow-green to dark green; com- 



