19. CYSTOPTERIS. 103 



70. D. (Steno.) Schlechtendahlii, Presl ; fr. 2-3 ft. 1., 1-2 ft. br. ; main rachis 

 stronfj, straight, naked ; lower pinnce 9-12 in. 1., 4-6 in. br., ovate-lanceolate, 

 spreading or deflexed, with a zigzag rachis ; pirinl. 2-3 in. 1., about 1 in. br., 

 cut down to a narrowly-winged strong rachis ; seffm. cut down to a centre which 

 equals in breadth the narrow linear forked or flabellate ultimate divisions ; 

 texture herbaceous ; sori small, terminal, suborbicular. — Ilk, iS'p. l.p. 189. t. 54. C. 



Hab. Mexico and Guatemala, ascending to 3-5000 feet. 



Gen. 19. CysTOPXERis, Bernh. 



Sori globose, placed on the back of the veins. Invol. membranaceous, subor- 

 bicular, inserted by its broad base under the sorus, which at the beginning it 

 covers like a hood. — Fronds small, two or three times divided, thin in texture, veins 

 free. Allied to Woodsia and Microlepia, aiid exceptional amongst the ferns in its 

 qeography, having its head-quarters in the Temperate Zones of both hemispheres. 

 Tab. II. f. 19. 



1. C. fragilis, Bernh. ; st. 2-4 in. 1. ; fr. 4-8 in. 1,, lJ-2 in. br., ovate-lan- 

 ceolate, tripinnatifid ; main race's slightly winged above ; largest /?2WW« 1-1^ in. 

 1., 5-| in. br., lanceolate-deltoid ; pinrd. oblong-rhomboidal, cut down to a broad 

 central space into bluntly- or sharply-toothed lobes ; texture herbaceous ; sori 

 2 to 12 to a pinnule. Hk. Sp. l.p. 197- Brit. Ferns, t. 23. 



Hab. Europe and Asia, everywhere from Iceland to Kamschatka, from the Arctic 

 regions to Madeira, and the Himalayas, where it ascends to 15,000 ft. ; mountains of 

 Abyssinia and Fernando Po ; South Africa ; Van Diemen's Land, New Zealand, 

 Sandwich Islands ; Temperate N. and S. America, and mountains in the intermediate 

 Tropical Zone. C. Tasmanica, Sandwicensis, and Douglasii, do not appear to be safely 

 separable. 



2. C. alpina, Desv. ; st. 2-4 in. 1. ; fr. 4-8 in. 1., 1-2 in. br., oblong-lanceolate, 

 tripinnatifid ; main 7'achis more or less winged above ; largest pinnce deltoid, 

 lanceolate, 1-1^ in. 1., ^-| in. br. ; pinnl. ovate-rhomboidal, cut down to the 

 rachis below into slightly toothed segm.; texture herbaceous; sori small, 2 to 12 

 to a pinnule. — Hk. Sp. \. p. 199. Brit. Ferns, t. 24. Aspid. Taygetense, Bori/ 

 and Chaub. 



Hab. Jlountains of Europe from Sweden to Greece and Spain, and Asia Minor. — In 

 England naturalized on a wall at Low Leyton, Essex. A more tender and usually more 

 finely-divided plant than the last, but often difficult to distinguish, 



3. C. hulbifera, Bernh. ; st. 4-6 in. 1. ; fr. 6-12 in. 1., 3-4 in. br. at the widest 

 part, ovate-lanceolate, often much elongated upwards, bi- or tripinnatifid ; lower 

 pinnl. lanceolate or ovate-lanceolate, 2-3 in. 1., 1 in. br. ; segm. linear-oblong, cut 

 down to the rachis below, very slightly toothed ; sori 2 to 12 to a pinnule, 

 usually in two rows, one in each segment. — Hk. Sp. 1. p. 199. C. atomaria, 

 Presl. 



Hab. N. America from Canada southward to Virginia and N. Carolina. — A very 

 distinct plant, which takes its name from the large fleshy bulblets which are formed in 

 the axils of the upper pinnae. These often fall to the ground and become new plants, 

 which, Prof. Eaton says, are about two years in coming to maturity. 



4. C. sudetica, A. Br, & Milde ; rhizome wide-creeping ; st. slender, 6-9 in. 1. ; 

 fr. 6-8 in. each way, deltoid, tri- or quadripinnatifid ; lowest pinnl. deltoid- 

 lanceolate, 1-H in. 1., less than \ in. br. ; lower segm. \ in. 1., 2 tin. br., ovate- 

 rhomboidal, deeply toothed ; texture herbaceous ; sori much larger than in 

 C. montana, only 2' to 6 to the lower segments.— i\^o». Act. vol. 26. P. 2. p. 554. 

 t. 44. 



