POLYTRICHACEAE 1 59 



b.2 



Catharinaeacrispa James occurs much less frequently 

 than the preceding species. Its favorite locality, like 

 C. undulata, is moist soil, especially banks of streams. 

 The leaves are usually light or yellowish-green, some- 

 what separated, hardly at all wavy, and the midrib is 

 narrow, about Ys the width of the leaf. 



Range, Canada and the northern United States; Europe. 



Catharinaea oris pa most closely resembles C. undulata 

 on account of the narrow midrib, but the leaves are more 

 separated, shorter and broader, and not at all or only 

 very slightly wavy, and they are usually a lighter green. 



The Catharinaeas may be distinguished from other 

 mosses that have long narrow leaves by the conspicuous 

 midrib and the leaves becoming strongly crisped wJien 

 dry. Tortella (p. 102) and Mnium hornum (p. 136) have 

 the leaves crisped when dry, but the midrib is not so 

 conspicuous, and the stems are thickly covered with 

 reddish-brown radicles which are not found on the 

 stems of Catharinaea. For comparison with Dicranum 

 and Polytrichum (two common genera having long 

 narrow leaves) see p. 171. 



If the leaves of Catharinaea are examined with a lens, 

 dark lines will be seen along the midrib. These are thin 

 strips of tissue called lamellae, characteristic of the 

 leaves of the Polytrichaceae, but not seen in other genera 

 without a compound microscope. See Plate VII, Fig. 3. 



