26 



ADIANTUM 



ADIANTUM 



AAA A A. Fronds at least hipinnate, often tripinnaie or 

 quadripinnate, with numerous rather small 

 fan-shaped or wedge-shaped leaflets with veins 

 radiating from the base. 

 B. Leaflets an inch or less across. 

 0. JEdges deeply cut into a series of narrow lobes. 

 18. Farleytase, Moore. Fig. 34. Fronds often reach- 

 ing 15-24 in. in length, forming a rich profusion of 

 closely overlapping pin- 

 nss, light green; leaflets 

 more or less wedge- 

 shaped at base, with cur- 

 Ted sides and the outer 

 margin rounded and 

 deeply out into 10-15 

 narrow lobes, which rare- 

 ly bear sori. Barbadoes. 

 I.H. 19: 92. -Said to be a 

 garden variety of A . te- 

 nerum, but apparently a 

 good species. 

 00. Edges not lacin- 

 iately cut. 



19. tfinerum, Swartz. 

 Fronds deltoid, 12-15 in. 

 long, two-thirds as wide, 

 the terminal leaflets 

 equally, the lateral un- 

 equally wedge-shaped at 

 base, all of them rhombic 

 and deciduous when dry, 

 with 10 or less small sori 

 on the outer and inner 

 margins. A. Z/clthomi,A. 

 TictSrice, A. rhodoph^l- 

 lu-iYi, A.princeps, and !k.. 

 Bausei are horticultural 

 forms. Fla. and Trop. 

 Amer. 



20. Jbrdani, C. Muell. 

 (A. emarg indium, D. C. 

 Eaton, not Hook.). 

 Fronds 1 ft. or more long, 

 6 in. wide, mostly twice 

 pinnate, with nearly 

 semicircular leaflets ; 



sori elongate, the indusium almost continuous around the 

 margin of the leaflet. Calif, and Oreg. 



21. ■WilUamsii, Moore. Fronds triangular, nearly 1 ft. 

 high ; leaflets nearly semicircular, 3-4-lobed on the outer 

 margin, bearing 5-8 sori covered with oblong indusia. 

 Peru. — Similar in habit to the last, but smaller and with 

 more numerous sori. 



BB. Jjeaflets mostly less than a half inch across. 

 c. Fronds at least quadripinnate, broader than long. 



22. Cdllisii, Moore. Fronds 1 ft. or more long, very 

 broad, the black rachises apparently repeatedly forking; 

 leaflets rhombic-ovate or cuneate, those towards the outer 

 portions longer and larger than those nearer the base.— 

 Of garden origin, possibly a hybrid. 



00. Fronds mostly triangular or oblong, longer 



than broad. 



D. Shape of leaflets rhombic, the indusia kidney-shaped 



or nearly circular. 



23. conclnnum, HBK. Fig. 35. Fronds 2-3-pinnate, 

 12-18 in. long, 6-9 in. wide, on rather stout black stalks ; 

 leaflets rhombic-oblong, slightly lobed; sori 4-8 on each 

 leaflet, usually set close together. Mex. to Braz. 



DD. Shape of leaflets roundish with obtuse base, small 

 or medium size. 



24. aithidpicum, Linn. (A.assimile, Swartz). Fronds 

 1 ft. or more long on slender stalks, 2-3-ptQnate, rather 

 narrow; leaflets roundish or obscurely 3-lobed, the mar- 

 gin finely serrulate ; sori 2-3 to a leaflet, with oblong or 

 kidney-shaped indusia. Afr. and Austral. 



25. excisum, Kunze. Fronds 2-3-pinnate, 6-12 in. long, 

 3-4 in. wide; leaflets about Jifiu. wide, roundish, with the 

 margin cut into small rounded lobes ; sori large, 2-4 to 

 each leaflet, kidney-shaped or circular. Chile. 



35. Pinna of Adiantum 



Natural size. 



concinnum. 



DDD. Shape of leaflets distinctly cuneate at the base. 

 E. Indusia oblong or indistinctly lunate, 



26. Capillus -Veneris, Linn. (A. Firgusoni, A. Mai- 

 risii, Moore). Fig. 36. Fronds 2-3-piniiate, 6-20 in. long, 

 3-8 in. wide; leaflets nearly Kin. wide, more or less ir- 

 regularly lobed at the outer margin ; sori 1-3 to each 

 leaflet, with oblong or more or less elongate narrow 

 indusia. Native southward, and widely distributed 

 throughout the Old World. — Exists in many varieties, 

 some of them deeply lobed, like A . Farleyense ; a com- 

 pact imbricated form is very effective. 



27. bfiUum, Moore. Small, 3-8 in. high, bipinnate ; leaf- 

 lets with the outer margin erose and often divided into 

 2-3 shallow lobes ; sori 2-3 to each leaflet, rather long 

 and broad or somewhat lunate. Bermuda. 



EE. Indusia nearly circular, with a narrow sinus. 



28. cuned.tum, Langs. & Fisch. (A. cemulum, A. m-An- 

 dulum, Moore. A. VersailHnse, A. fragrantissimum, 

 Hort. ) . Fronds 3-4-pinnate, deltoid, 6-15 in. long, 5-9 in. 

 wide ; leaflets numerous, obtuse or broadly wedge-shaped 

 at base, the margin rounded and more or less crenately 

 lobed ; sori 3t-5 to each segment, with rather small rounded 

 indusia. Braz. — Runs into many forms, of which A . va- 

 riegdtum is one. 



29. Modrei, Baker {A. amdbile, Moore, not Liebm.). 

 Fronds 2-3-pinnate on long slender stalks, 6-15 in. long; 

 leaflets K-J^in. long, rhomboidal, with wedge-like base, 

 deeply lobed ; sori of medium size, 4-6 to each leaflet. 

 Peru. 



30. "WAgneri, Mett. {A. decorum, A. Wiigandi, A. ile- 

 gans, A . Oweni, A . cyolosdrum, Moore) . Fronds 2-3-pin- 

 nate, 6-9 in. long, 4-6 in. wide; lateral leaflets rhomboid, 

 the terminal cuneate, slightly lobed or incised ; sori 4-6 

 to each leaflet, with very large membranous circular in- 

 dusia. Peru.— A. Si^bi'echtii, Hort., "supposed to be a 

 cross between A. decorum and A. WilUamsii," has 

 strong, graceful fronds thickly set with round pinnules 

 of firm texture. 



31. rub611um, Moore. Fronds 4-6 in. long, deltoid, bi- 

 pinnate ; texture membranous, bright green, reddish 

 when young ; leaflets Xin. wide, deltoid or the lower 

 rhomboid, the outer margin deeply lobed and the lobes 

 finely toothed ; sori round at the apices of the lobes. 

 Bolivia, 



36. Pinna of Adiantum Capillus-Veneris. Natural size, 



