FiLiCES. (ferns.) 685 



stalked (2-5" long), from narrowli/ rniiealt to rounf/ish-fthovate, toothed or in- 

 cised at tlioapcx; veins forking; sori 2-4 on a sc;j;nu'nt. — Liniestone diffa, 

 Vt. to Mich., and southward ; scarce. July. (Ku.) 



* * * * Tall ferns (2-4° hiyh), not evergreen; fronds pinnate or sub-bi pinnate. 



10. A. angUStifblium, Michx. Fronds thin, simply pivnnte ; pinnae 

 numerous, short-stalkod, linear-lanceolate, acuminate, entire or crenulate (3-4' 

 long), those of the fertile frond narrower; fruit-dots linear, 20-40 each side of 

 the midvein ; indusia slightly convex. — Rich woods, W. New Eng. to Wise, 

 and soutlnvard along the mountains. Sept. 



11. A. thelypteroides, Michx. (I'l. 18, fig. l, 2.) Fmnds (2-3° 

 high) pinnate ; pinmr deejili/ pinnatifd, linear-lanceolate (3 - 5' long) ; the lobes 

 ol)long, obtuse, minutely toothed, crowded, each bearing 3-G pairs of oblong 

 fruit-dots, some of them double. — Kich woods ; not rare. July - Sept. 



§ 2. ATHYRIUM. Indusium delicate, curved, often crossirfg the vein, and at- 

 tached to both sides of it, thus becoming reniform, or shaped like a horseshoe. 



12. A. Filix-fcemina, Bemh. Fronds (1-3° high) ovate-oblong or 

 broadly lanceolate, twice j)innate ; pinna lanceolate, numerous ; pinnules con- 

 fluent on the secondary rhachis by a narrow margin, oblong and doubly serrate, 

 or elongated and pinnately incised with cut-toothed segments ; fruit-dots short, 

 variously curved, at length confluent, — Moist woods ; common and presenting 

 many varying forms. July. (Eu.) 



10. SCOLOPENDRIUM, Smith. Hart's-Toxgue. (PI. 18.) 



Fruit-dots linear, elongated, almost at right angles to the midrib, contiguous 

 by twos, one on the upper side of one veinlet, and the next on the lower side of 

 the next superior veinlet, thus appearing to have a double indusium opening 

 along the middle. (The ancient Greek name, so called because the numerous 

 parallel lines of fruit resemble the feet of the centipede, or Scolopendra.) 



I. S, VUlgkre, Smith. Frond oblong-lanceolate from an aurided-heart- 

 shaped base, entire or wavy-margined (7-18' long, 1 -2' wide), bright green. 

 — Shaded ravines and under limestone cliffs ; central N. Y. ; also in Canada 

 andTenn.; very rare. Aug. (Eu.) 



II. CAMPTOSORUS, Link. Walking-Leaf. (PI. 18.) 



Fruit-dots oblong or linear, as in Asplenium, but irregularly scattered on 

 either side of the reticulated veins of the simple frond, those next the midrib 

 single, the outer ones inclined to approximate in pairs (so that their two indu- 

 sia open face to face), or to become confluent at their ends, thus forming crooked 

 lines (whence the nanio, from Kafxtrros, bent, and crupos, ior fruit-dot.) 



1. C. rhizophyllus, Link. Fronds evergreen, sub-coriaceous, growing 

 in tufts, spreading or procumbent (4-12' long), gradually narrowed from a 

 cordate or auricled base to a long and slender acumination, which often roots 

 at the end and forms a new plant. — Sliaded rocks, cs])ecially calcareous rocks^ 

 N. Eng. to Minn., and southward to Kan. and Ala. — The auricles are some- 

 times greatly elongated, and even rooting; in another form they are lacking, 

 as in the thinner leaved C. Sibiricus. July. 



