RARE LOCAL FERNS. 39 



the more common species. Keller and Brown give nine local- 

 ities in six counties of South-eastern Pennsylvania. One of 

 these is at Conshohocken, another at Coatesville. We may 

 add to these one more. In 1882 it grew in the ravine near the 

 eastern end of the high railroad bridge west of Media. With 

 it were Os7mt?ida cinnamomea, Dickoiiia and other fern species, 

 including some of the genus Aspidium. The fronds bore 

 almost no indication of the bulblets that give the fern its spe- 

 cific name, and it was only by a careful examination of the 

 other characters that its identity was fixed. The vicinity has 

 undergone some changes, and it is not at all certain that the 

 fern has survived. But there are many shady ravines here- 

 abouts, and while this part of Pennsylvania is on the very 

 edge of the range of this species, it may still lurk here and 

 there. Another species of the same genus, Filix fragilis, is a 

 species of almost world-wide distribution. However, it is 

 here near its south-eastern limit. It is scarcely known to 

 occur in Southern New Jersey. It is discoverable among 

 the shaded cliffs along the larger streams down to the ancient 

 shore line of the Delaware Bay, known now as the "180 foot 

 contour above tide." Below that point, riverward, where the 

 conditions are somewhat similar to those in New Jersey, it is 

 rare or absent. It may be said to belong to the Piedmont 

 Plateau, and not to the Coastal Plain. 



By contrast, the chain ferns are in this region distinctly of 

 the Coastal Plain. Woodzvardia areolata, the rarer of the two 

 in Pennsylvania, is quite common in New Jersey, where it 

 thrives especially in inundated, shaded places. It is recorded 

 from Tullytown, in Bucks county, and from Tinicum. The 

 Tinicum locality was mentioned in Dr. George Smith's origi- 

 nal list of Delaware county species, and specimens from there 

 are in the herbarium of the Institute. It is impossible to say, 

 now, whether the fern was once abundant in Tinicum. For 

 many years past it has apparently been confined to two 

 closely associated places. One of these is on the edge of a 

 woodland between Lester and the pond known as Long Hook. 



