POLYPODllJM, § CYRTOMIPIII.ERIIJM. 1") 



ous vein or spurious costule, sori small solitary near the mid- 

 dle of the veinlets. 



Ilab. Dunk Island, N.E. coast of Australia, MactjilUvray, Voij. of the Rattle- 

 snake. — A very distinct peculiar specieS: but as the sori are in a measure obli- 

 terated I cannot be sure of its being exinvolucrate. Habit of some of the Cyrto- 

 mium group, but the venation more that of Goniopteris, only the basal veinlets 

 (and sometimes the next pair) are always free. 



§ 4. CvRTOMiPHLEBtuM. — Habit and venation o/'Cyrtomium. Sp. 250. 



250. p. (Cyrtomiphlebium) dubium, Hook. ; caudex short 

 thick erect crowned with a dense mass of imbricated subulato- 

 lanceolate jet-black glossy scales i-f inch long brownish at 

 the margin, stipites tufted 1-2 feet and more long firm stout 

 stramineous the base clothed with the scales just described 

 the rest as well as the rachis paleaceous with thin membra- 

 naceous ferruginous lacerated subovate scales, fronds 1-2 and 

 3 feet long firm subcoriaceous glabrous pinnated scarcely 

 pinnatifid at the apex, pinnte 3-5-6 inches long 'i-lh inch 

 wide from a broad cuneate base truncated and auricled above 

 ovato-lanceolate subfalcate serrated or bipinnate in the lower 

 half and then elongated G-9 inches long uppermost ones pin- 

 natifid and strongly lobed at the margin, pinnules 1-1 1 inch 

 long rhomboid acute sharply serrated towards the point, 

 veins or veinlets all diverging from the costa erecto-patent 

 forked and anastoi^iosing into very elongated areoles rarely 

 except towards the apex and at the margin free, sori irregular 

 varying in size subrotund or oval dorsal on the free or anasto- 

 mosing veinlets. — Phegopteris, /var^^. FL Coluinb. v. \. p. 109. 

 /. 84. — Var. a, fronds pinnate. — Var. /3, fronds bipinnate. 



Hah. o, Peru, ex Herb. Ruiz and Pavon. Ecuador, Jameson. Mount Tungu- 

 ragua, Spruce, n. 5264 and 5265 (sori very large oval). y8, Andes of Ecuador, 

 Spruce, n. 5263. Bogota, Karsten. — In the course of my investigation of the 

 Polypodieous Ferns ! am frequently startled with the appearance of species which 

 have little or nothing to distinguish them from others in the Aspidieous group 

 save that the sori are destitute of involucre. Such is the case with the one now 

 under consideration ; yet so great is its resemblance to the East Indian Aspid. 

 (Cyrtomium) caducum. Wall., that Moore, in his hid. Fil., refers these South Ame- 

 rican Ferns of Spruce to the A. caducum. Besides, however, the exinvolucrate sori 

 (and if otliers liad overlooked them in the dried state, Mr. Spruce, who has 

 sent the specimens as true " Poli/podium," could not have done so in the living 

 state), there is a different form in the rhomboid pinnules, and there is a difference 

 in the venation, on which Mr. Moore will lay more stress than I have the credit 

 of doing. In P. dubium, in the i)innated form, the veins anastomose more than 

 in Aspid. caducum (where sometimes the pinnae are all free-veined), the free 

 veinlets which do appear are never within an areole, nor do these ever bear a ter- 

 minal sorus, and in the pinnules of the bipinnate froiuls the venation equally 

 anastomoses. Time aiul experience may teach us the true value to be placed both 

 on the venation and the involucre. 



