156 ACOTYLEDONS. FILICES. FlcriS. 



5. A. altcrnifoUum, fronds pinnate, pinnules alternate laiiceo- 

 lato-cimcate toothed at the apex, lower ones trifid and tooth- 

 ed. E. B. t. 2258. J. germanicum, Willd. 



llxn. Sunny rocks in the south of Scotland, about two miles frora 

 Kelso, on the Tweed, Dickson. (In Switzerland it is quite an al- 

 pine plant.) 



6. A. Rata- mur aria, fronds bipinnate at the base, pinnules cu- 

 iieate obtusely toothed at the extremitv. Light/, p. 665. 

 E. B. t. 150. 



Hab. Wails and the fissures of rocks, frequent. 



7. A. Adlnntum wgruin, fronds bipinnate, pinnae oblongo-lan- 

 ccolate acute, pinnules oblong inciso-pinnatifid, the segments 

 toothed at the apex, sori at length confluent. Lightf. p. QQ^. 

 E.B.t. \950. 



Hab. Banks in shady places, and fissures of rocks, frequent. 



6. SCOLOPExNDRIUM. 

 Sori linear, transverse, scattered. Involucre double, occupying 

 both sides of the sorus, superficial, and opening as it were by 

 a longitudinal suture. 



1. S. vulgare. E.B.t. 1150. Aspltiman Scolopendrimn, 



Lightf. p. 6G0. 

 Hab. Shady, rocky, or stony places. 

 Frond ligulate, acute, entire, cordate at the base. 



7. PTERIS. 

 Sori continuous, linear, marginal. Involucre formed of the in- 

 flexed margin of the frond opening interiorly. 



1. Pt. crispa, sterile fronds bipinnate, pinnules pinnatifid, the 

 segments obovato-crenate inciso-dentate at the extremity, fer- 

 tile fronds bipinnate tripinnate below, pinnules linear oblong 

 rather obtuse entire narrow at the base. E. B. I. 116. Os~ 

 inunda crispa, Lightf. p. 655. 



FUb. Among rocks and stones in the Highland mountains. Ben-na- 

 Caillich in Skyc, Lightf. Salisbury craigs, Mr. Stuart. Birnam 

 hill and near Cluny, Mr. Arnott. Goat-fell, in Arran, sparingly ; 

 on Ben Nevis, plentifully, Mr. Murray. Western Lomond HiH, 

 Fifeshire ; and near New Abbey, in Galloway, Maugh. 



2. Pt. aquilina, frond tripartite, branches bipinnate, pinnae li- 

 near-lanceolate, superior undivided, inferior pinnatifid, the seg- 

 ments oblong obtuse*. JE. J5. /. 1679. Lightf. p. 657. 



' I arn happy in having the opportunity of publishing here some remarks 

 upon the structure of the fructification of this plant, which have been kindly 

 communicated to me in a letter from Thomas Smith, Esq. of the Temple, 

 London. They allude to a real inrolucrtim distinct from that formed by the 

 involution of the margin of the /rnnd. " This," Mr. Smith says, " will be 

 found exactly oppositp to thut which Is seen on the edgt- of the frond, and. 



