498 



FILICES. 



ASPIDIUM. 



An erect straight fern about a foot and a half high, growing in clusters. Stipe and rachis 

 very chaffy, with lanceolate scales. Frond lanceolate in the outline : sterile pinnules or 

 segments alternate, 1-2 inches long, each on a very short stalk, with a conspicuous triangular 

 auricle at the base on the upper side ; the serratures ending in a short bristle : fertile segments 

 much smaller than the sterile, constituting the upper part of the frond. Sori rather large, 

 arising from the extremity of all the veinlets but the terminal ones, at first somewhat distinct, 

 finally confluent, and forming a thick covering to the lower part of the segment. Involucre 

 orbicular-reniform. 



Shady rocky hill-sides : common ; the variety incisum, in shady ravines near Hamilton 

 College (Dr. Gray). Fr. June - August. 



8. Aspidium aculeatum, Swart z. Prickly Shield-fern. 



Frond bipinnate ; pinnules ovate, somewhat falcate, slightly petioled, acute, mucronately 

 serrate, truncate and auricled at the base on the upper side, obtusely cuneate on the lower, 

 upper ones fructiferous ; stipe and rachis chaffy. — Swartz, I. c. ; Willd. sp. 5. p. 258 ; 

 Pursh, fl. 2. p. 662 ; Hook. Brit. fl. (ed. 4.) 1. p. 384, $ fl. Bor.-Am. 2. p. 261 ; Tuckerm. 

 in Sill. jour. 45. p. 46. 



Stipe 2-6 inches long, thickly clothed, as is also the rachis, with long chaffy lanceolate- 

 subulate scales. Frond H - 2 feet long and 4-6 inches wide, of a somewhat rigid texture, 

 broadly lanceolate in the outline ; the pinna? lanceolate ; the lower ones gradually diminishing 

 in size : pinnules or segments 6-8 lines long, sparingly chaffy-pilose underneath ; the teeth 

 ending in a short bristle. Sori rather large, 6 - 8 on each pinnule, near the middle. Involucre 

 reniform-peltate. 



Mountains of Essex county (Dr. W. F. Macrae). I was not so fortunate as to find this 

 interesting fern when I explored the Essex mountains ; neither was it detected by Dr. 

 Knieskern, in his subsequent visit to that region. My specimens are from the Green Mountains 

 of Vermont (where the plant was first found in N. America, by Pursh), and the White 

 Mountains of New Hampshire ; the former kindly communicated by Dr. W. F. Macrae, the 

 latter by Mr. Tuckerman : both presenting an exact resemblance to the European A. aculeatum. 



13. ONOCLEA. Linn.; J. Smith, I. c. no. 82. SENSITIVE FERN, 



[An ancient name of a Borragineous plant, applied, without evident reason, to this genus,] 



Ragiopteris, Presl. 



Fertile frond bipinnate ; the pinnules contracted ; the segments incurved and berry-like, 

 constituting a general involucre. Sori round, 4-6, confluent. Proper involucre lateral, 

 cucullate, thin and membranaceous. Sterile fronds deeply pinnatifid ; the segments 

 sinuous or pinnatifid, with reticulated veins. Fertile fronds small ; the pinnules much 

 contracted, forming an unilateral raceme of globose segments, which are filled with the 

 capsules of the confluent sori. 



