132 Ferns of T amalpais. [ZOE _ 
16. PELLAA DENSA, with its finely-divided segments, is found 
on rocks near Mr. Liberty’s house, so near the road that they may 
be plucked in passing. It is found in similar dry, rocky localities 
on that side of Tamalpais, especially below the higher summit. 
17. PELLAA ANDROMEDAFOLIA, with its reddish stems and 
small pinules, has been popularly, but erroneously, called ‘‘ Red 
Maiden Hair.’’ It usually seeks its home under the partial shade of 
some shrub or tree, which affords its brittle fronds protection as well. 
It is to be found at low elevations, while P. densa and P. ornithopus — 
seek height; the former usually growing a thousand feet or more 
«above sea level. 
18. PELLAA ORNITHOPUS, with its finely-divided, stiff, grayish 
and erect fronds, seeks the dryest and most barren rocky places, 
fully exposed to the sun. It is found at various places on the rocky 
ridge leading from Tamalpais to Bolinas Ridge, and is an ex- 
tremely variable fern. One can find forms of widely differing widths 
according to habitat, but the very long and narrow forms have been _ 
placed in a separate species and called P. brachyptera, which, how- 
ever, in its typical form, is not, to my knowledge, found in the 
county. 
The Pellzas are all rock lovers, with coriaceous leaves, and are 
commonly called “‘ Cliff’ or ‘Rock Brakes.” 
19. PTERIS AQUILINA, knownas “ Brake,” “ Bracken,” or ‘‘ Ea- 
gle Fern,’’ may be found everywhere—on open hillside, in field or 
meadow. It usually seeks good soil, and luxuriates in it. In some 
other counties it attains a great height, spreading in a manner most | 
alarming to the farmer, who is unable to get rid of it in any way. 
This must be the black sheep of this charming order of plants, | 
whose characteristics are to be described by only the most agreea- 
ble adjectives in most other cases. 
20. GYMNOGRAMME TRIANGULARIS I have left to the last. 
This little plant is distinctively Pacific, and dear to the heart of 
every lover of ferns. Everyone knows the ‘‘ golden-back,’’ and ~ 
knows where on shaded banks to seek it. Its beautiful little tri- 
angular fronds of glossy green, with their powdered under surfaces 
and elegantly polished black stipes, are familiar to most of us. 
A second form of it is found in Yosemite and in the southern part 
