342 FILICES. Adiantum. 



8. ADIANTUM, Linn. MAIDENHAIR. 



Sporangia borne at the ends of the veinlets, on the under (inner) side of the re- 

 flexed margin of the frond, the involucre thus formed being either continuous or 

 interrupted or divided into small and widely separated lobules. Midvein of the 

 ultimate pinnules mostly excentric or lateral, or the forking and usually free veinlets 

 rising directly from the end of the petiolule of the segments. Stalk mostly black- 

 ened or very dark purplish-brown, and commonly highly polished. 



Sixty-seven species are described by Keyserling, in his excellent monograph on this genus, pub- 

 lished in Mem. Acad. Sci. St. Petersb. vii m< serie, tome xxii, No. 2. A few tropical species have 

 simple roundish fronds, others are simply pinnate, and the remainder are variously 2- 4-pinnate 

 or decompound, but never dissected into narrow segments. 



* Fronds pyramidal in outline, 2 ^-pinnate at the base ; main rhachis continu- 

 ous to the apical pinnule : veins dichotomous, the veinlets extending to the ends 

 of the teeth of the segments. 



1. A. Capillus-Veneris, Linn. (VENUS-HAIR.) Plant 4 to 24 inches high, 

 often pendent : stalks and rhachises very slender, nearly black, polished : fronds 

 elongated-pyramidal, thin, smooth, simply pinnate towards the apex, 2 - 3-pinnate 

 below; pinnules and upper pinnae rather long-stalked, 6 to 15 lines long, rhomboid 

 or roundish-obovate, cuneate at the base, somewhat palmately lobed or incised ; the 

 ends of the lobes crenately or acutely denticulate except where the margin is recurved 

 to form the lunulate or transversely oblong separated involucres. Hooker, British 

 Ferns, t. 41 ; Eaton, Ferns of N. Amer. i. 281, t. 37. 



Damp and shady places in the canons of the southern part of the State (G. W. Dunn, Mr.". 

 C'oope.r, Mrs. Bagg, Dr. Rothrock), and eastward to Utah, Texas, Missouri, and the Atlantic 

 States from Virginia to Florida. Also in Europe, Asia, Africa, South America, etc. ; a well- 

 known plant, formerly used in preparing "Sirop de Capillaire," a popular cough-remedy. 



2. A. emarginatum, Hooker. Plant a few inches to two feet high, usually 

 erect : stalks rather stouter than in the last, nearly black, polished, about half the 

 whole height of the plant : fronds broadly ovate or deltoid-pyramidal, simply pinnate 

 towards the apex, 2 3-pinnate below ; pinnae obliquely spreading, lower ones half 

 as long as the frond ; pinnules long-stalked, 4 to 15 lines broad, roundish or semi- 

 circular or even reniform, the lower sides entire, the outer edge rounded, slightly 

 2 - 5-lobed, finely and sharply toothed in the sterile fronds, but in the fertile re- 

 curved and forming pale transversely elongated involucres. Sp. Fil. ii, t. 75, A ; 

 Keyserling, 1. c. -15, 37; Eaton, Ferns of the Southwest, 325, and Ferns of N. 

 Amer. i. 285, t. 38, fig. 1-3. A. Chilense of American authors, not of Kaulfuss. 

 A. jEthiopicum, in part, Baker, Syn. Fil. 123. 



Among rocks in canons, both dry and moist, common in the Coast Ranges from San Diego to 

 Oregon, but scarcely known in the Sierra Nevada. Keyserling has well distinguished this species 

 from the others related to it. Hooker's figure, although said to be taken from a Mauritius plant, 

 well represents only our species, and was probably drawn from a Californian specimen. A pubes- 

 cent Adiantum (A. dilatatum, Nutt. MS. in Herb. Hook.), reported from near Monterey by Nut- 

 tall, has not been collected since his time : it may have been A. tridiolepis, Fee ( Eaton, Ferns of 

 the Southwest, 326), or a hairy form of the present species, or something different from both. 



* * Fronds rounded-fan-shaped in outline, the stalk forking at the top, the forks 



recurved and each bearing several pinnate branches oit the upper side. 



3. A. pedatum, Linn. Stalks dark-brown or blackish, polished, a foot or more 

 high, forked at the top, the two branches divaricate and obliquely recurved, bearing 

 on their upper or outer sides 6 to 14 long spreading pinnate divisions : pinnules 

 numerous, short-stalked, thin, smooth, oblong or triangular-oblong, the lower margin 

 entire and often hollowed out, the base parallel with the polished hair-like rhachis, 

 the upper margin lobed or cleft and bearing a few oblong-lunate or transversely 



