Pteris. FILICES. 341 



f'lcfts of rocks in tlic Siorra Nevada, mostly at from 6,000 to 9,000 font clnvation. The \inilcr 

 ainlnce of tlii; from! Homctiiiu's l)cars a trace of tlio same yellowish waxy [lowilor seen in many 

 species of Gijmnotjramme and Kotholvcna. 



r. KLEXUOSA, with fiexuons rhachis and rather large cordate-ovate pinnules occurs in Arizona, 

 and may yet be discovered in the southern part of California. P. gracilis and P. atropurpurca 

 are well-known species of tiie Eastern States. 



6. CRYPTOGRAMME, R. Brown. Kock-I3r.\kk. 

 Sporangia on the back or near the ends of the free veins, forming oblong or 

 roundish, and at length confluent sori : involucres continuous, formed of the mem- 

 branaceous and somewhat altered margins of the pinnules, at first reflexed and meet- 

 ing at the midrib, at length opening out flat. I'ronds rather small, herbaceous, 

 smooth, dimorphous, 2-4-pinnate, the fertile ones taller than the sterile, and with 

 narrowly elliptical or obloug-linear pod-like segments. Stalks stramineous, tufted on 

 a short rootstock. 



A genus of only two species, C. crispa of Europe, and the following. 



1. C. acrostichoides, W. Ih-own. Kootstocks short, creeping, chaffy : stalks 

 densely clu.stcre(l : li-onds chartacoous, ovate, 2-3-pinnate, 2 to 4 inches long; 

 sterile ones short-stalked, having narrowly winged rhachiscs, idtimato segments 

 crowded, ovate or obovate, adnate-decurrent, crenatcly toothed or slightly incised ; 

 fertile fronds long-stalked, the rhachises scarcely winged, nltimate segments oblong 

 or linear-oblong, 3 to 5 lines long, scarcely one line wide ; involucres very broad : 

 sori oblong, extending down the forked veinlets almost to the midvein. — Hooker 

 k Greville, Ic. Fil. i, t. 29; Eaton, Ferns of N. Ainer. ii. 91), t. 59, fig. 1-5; 

 Williamson, Fern Etchings, t. 7. Allosorus acrostichoides, Sprengel ; Gray, Manual. 



Common among rocks at high elevations, extending to Colorado, Lake Superior, the Aleutian 

 Islands and Arctic Ameiica. Tiie fronds are more rigid and less compound than in C. crispn, and 

 the sporangia arc not limited to the upper part of the vidns, as they are in that species. But sev- 

 eral able botanists consider the two as forming but one species. 



7. PTERIS, Linn. Biiackkn. 

 Sporangia seated on a continuous vein-like marginal receptacle, which connects 

 tho ends of the veins : involiK^ro oxtoniling around the margins of the sogmonts, or 

 sometimes interrupted at their apices, and sometimes double. Fronds, in the only 

 Californian species, ample and decompound, tho veins Uw,. 



A large genus, having many tropical species, with fronds varying from simple to decompound, 

 the veins free or variously leticulated. Stalks commonly light-colored. 



1. P. aquilitia, Linn. Kootstock blackish, cord-like, creeping widely under- 

 ground : stalks solitary, Crect, naked, swollen and di.scolored at the base : frond 

 sometimes 3 feet long and nearly as broad, rigidly sid)coriaceous, smooth or pubes- 

 cent, triangular-ovate in outline, 2-4-pinnate at tJie base; principal i)rimary pinn;u 

 stalked, the lowest ones very large, the rest rapidly becoming smaller ; pinnules 

 oblong-lanceolate or linear, entire, hastate, or piunately parted ; segments oblong or 

 linear, obtuse, the terminal ones often elongated ; veins close-placeil, free, repeatedly 

 foiking. — l':aton. Ferns of N. Amer. i. 2G3, t. 35 ; Williamson, Fern Etchings, t. 10. 



Var. lanuginosa, Bong. Lower surface of the frond decidedly pubescent or 

 silky-tomentoso, tlie segments broad. — Veg. Sitch. 170. 



Very common throughout the State, extending northward to Sitka and eastward to Utah. In 

 Northern California and Oregon it fonns thickets six or seven feet high and several acres in ex- 

 tent. The plant of the Eastern States is less imbescent or Jiearly smooth. The bracken is the 

 most widely distributed of all ferns, and in many parts of tho world either the young fronds, when 

 boiled, or the rootstocks after roasting, have served as articles of foo.l. The mature fronds have 

 been used for thatching, and the ashes for scouring or for making domestic soap. 



