138 FLORA OF THE UPPER SUSQUEHANNA. 



D. Qoldieana (Hook ) A. Gray. Goldie's Shield-Fern. Rare. 

 In swampy ground east of Van Etten. Chemung county, N. Y., 

 Barbour. Near Unadilla Forks; not common, Brown. The 

 only stations. This fern may occur at other points within our 

 limits and should be looked for in cold, wet woods. In appear- 

 ance it IS considerably like the following and might be mistaken 

 for a large form of it. {Aspidium Goldieana Hook.) 



D. marginalis (L.) A. Gray. Marginal Shield-Fern. Ever- 

 green Wood-Fern. Abundant in deep shades. Fronds two 

 feet or more high, about twice pinnate. Well known for the 

 bright, white covering to the fruit dots, which are borne on the 

 back of fronds like the sterile ones. The fronds remain green 

 through the winter, but are usually prostrated by wind and 

 snow. {^Aspidium margma/e Swartz. ) 



D. acrostichoides (Michx.) Kuntze. Christmas Fern. Abun- 

 dant throughout our range, especially in evergreen woods. 

 Fronds thick, evergreen, pinnate, the fertile contracted at the 

 summit. Among the earliest of our ferns to fruit. The variety 

 incisa is occasionally found with the type, and differs from it in 

 having the pinnte much incised and in fertile fronds, nearly all 

 of them fruit-bearing. This species is one of our best known 

 ferns and is much used for holiday decorations. {Aspidium 

 acrostichoides Sw. ) 



CYSTOPTERIS Bernh. 



C. bulbifera (L.) Bernh. Bilb-Bearing Bladder-Fern. Some- 

 what rare. Oxford, Coville. Killawog, N. Y. , Clute. Cascade, 

 near Susquehanna, Graves. North of Apalachin, Fe?ino. Ra- 

 vines at Unadilla Forks. Brown. Elsewhere not reported. 

 Found usually on cliffs. Fronds very long and narrow, prostrate 

 or pendant, bi-pinnate. In addition to fruit dots, the fronds 

 usually bear bulblets on the backs. 



C. fragilis (L.) Bernh. Fra(;ile Bladder-Fern. Brittle Fern. 

 Common in wet, shaded soil, especially on cliffs. Fronds 

 rather slender, nearly a foot long, twice or thrice pinnate. 



ONOCLEA L. 

 O. sensibilis L. Sensitive Fern. Very abundant. Found on 

 the borders of ponds and streams and in all low grounds. Ster- 

 ile fronds broad and coarse; fertile fronds later in the season. 



