THE ROCK SPLEENWORTS. 159 



borne on the backs of ordinary fronds, several on each 

 pinnule and slightly nearer to the middle than the 

 margin. The indusium, of course, is linear. 



In the eastern United States, the green spleenwort is 

 found only in Vermont. Further north it is slightly 

 more abundant and is generally distributed throughout 

 British America, reappearing in our Western States in 

 the mountains of Oregon, Wyoming and Washington. 

 It is also found in Greenland and in the colder parts of 

 the old world. Over seas this species grows with the 

 maindenhair spleenwort and in our own country selects 

 much the same habitats. It is occasionally called green 

 maidenhair. We illustrate a Vermont specimen. 



The Small Spleenwort. 



The small spleenwort (Asplenium parvulutri) is a south- 

 ern species which careless collectors might gather for 

 the maidenhair spleenwort or perhaps the ebony spleen- 

 Wort. It grows in tufts on shaded, or sometimes on 

 sunny cliffs, the fronds spreading from a short half-erect 

 rootstock. The stipe and rachis are very dark brown 

 and polished but are much more rigid than in the maid- 

 enhair spleenwort. The fronds are also thicker, almost 

 leathery in texture and much broader. 



In shape the fronds are linear-lanceolate and once pin- 

 nate with many pairs of opposite, oblong, blunt pinnules 

 that are usually slightly eared on the upper side at base. 

 In the larger fronds, which may occasionally reach a 

 length of ten inches, there is a tendency to produce an ear 

 on the inferior bases of the pinnules also. This is espe- 

 cially noticeable in the shortened lower pinnules which 

 thus often become triangular. The sori are borne on 



