FERN FAMILY 67 



The fronds are sweet-scented when crushed 

 or while drying, and often emit a delicious fra- 

 grance in the field. They are sensitive to early 

 frosts, and frequently bleach nearly white in 

 autumn. 



Other names for it seem to abound. It is 

 known as the Boulder Fern, Fine-haired Moun- 

 tain Fern, Hay-scented Fern, and Sweet-grass 

 Fern. 



The fertile and sterile fronds are similar in 

 form. The fruit-dots are small, each on a re- 

 curved toothlet, usually one at the upper mar- 

 gin of each lobe. They mature in July. The 

 indusium is cup-shaped and open at the top. 



Var. C}istata. 



This is a local form discovered in Massa- 

 chusetts. It grows with the type, and is notice- 

 able for the forking of the ape.x of the frond 

 which is sometimes crested. The same pecu- 

 liarity frequently occurs in the pinnae. 



CYSTOPTBRIS. Bladder Pern. 



The name is from the Greek kiistis, a blad- 

 der, and pteris, a fern, alluding to the inflated 

 indusia. This group was formerly classed in 

 the genus Aspidium. 



