10 



FERNS : SYNOPTICAL LIST.— XIII. 



Synoptical List, with description, of the Ferns and Fern- Allies of Jamaica, by O. 8. Jenman, Superin- 

 tendent Botanical Gardens, Demerara, (continued). 



Tribe vi. — Pteridea. 



Sori marginal, punctiform but often confluent, crescent-shaped or linear ; involucres exterior, the 

 form of the sori. 



11. Hypolepis. — Sori dot-like, situated in the sinuses, covered by a crenature of the margin or a 

 distinct involucral scale. 



12. Notholcena. — Sori of few sporangia, at length confluent, supported but not f ally covered by 

 the margin. 



13. Cheilanthes. — Sori dot-like, isolated or confluent, involucres the same form covering a single 

 on several sori. 



14. Pellea. — Sori confluent, linear, involucres the same form. 



15. Plagiogyria. — Sori roundish, on the forked summits of the veins, at length confluent, involu- 

 cres linear uninterrupted. 



16. Lonchitis. — Sori chiefly crescent-shaped, and confined to the sinuses and hollows of the lobes, 

 involucres the same form. 



17. Pteris. — Sori linear, uninterrupted, involucres the same form. 



The features which characterise this tribe are the marginal sori seated on the apices of the veins, 

 or (in other cases) running transverse, on a special very slender receptacle, with the summits of few 

 or many veins, together with the exterior attachment of the involucres, which consequently open in- 

 teriorly — i. e. on the side nearer the centre of the leaf or leaflet. In other characters the Tribe pre- 

 sent great diversity. 



Genus XI. Hypolepis, Bernh — Sori marginal, in roundish isolated dots, in the hollows of the 

 final lobes or teeth, terminal on the club-like summits of the lower exterior veinlets ; involucres 

 formed of the reflexed crenatures of the' margin, changed or not into pale reniform membranous 

 scales ; fronds decompound, veins free, rootstock free-creeping. 



The affluent size of the fronds and basal situation in relation to the lobes of the sori, which are 

 borne only on the lower exterior veinlets instead of on all, are the only characters which define this 

 genus from Cheilanthes ; while, when mature, and the involucral crenatures have opened out, the 

 members can barely be distinguished from Polypodium, one local species of which — P. punctatum — 

 identically resembles in conformation and habit one or two of the species. 

 a. Fronds medium sized, not prickly. 



1. PL. Purdieana, Hook. 



aa. Fronds ample, prickly (one variety excepted). 



2. H. repens, Presl. 

 aaa. Fronds ample, scandent, prickly. 



3. H. nigrescens, Hook. 



1. H. Purdieana, Hook. — Rootstock as thick as a quill, free-creeping, dark scurfy ; stipes 

 scattered, \ — 1 ft. 1. or more, glandulose — pubescent, chesnut, rather glossy channelled; fronds her- 

 baceous, dark green, tri — or quadri-pinnate,l — 2\ ft. 1. f — 1£ ft. w. ovate — lanceolate, rachis and costaa 

 freely glandulose pubescent and castaneous, other surfaces also slightly glandulose — ciliate, chiefly 

 the upper on the costulae and the final ribs, which are flat ; pinnae \ — 1 ft. 1. 2-5 in. w. ovate — lanceo- 

 late, opposite, the lowest pair most distant ; pinnulse oblong — lanceolate, pointed, but not acuminately ; 

 final segments oblong, dentate or inciso — dentate, 2-4 li. 1. 1£ li. w. obtuse ; sori at the base of the 

 ultimate lobes or teeth, covered at first by a marginal crenature. — Hook. Sp. Fil. Vol. 2, t. 91. B. 



Common on the ridges and peaks above 6,000 ft. alt. A smaller plant than any of the forms of 

 repens, very glandulose and sticky when fresh, but not prickly, of dark colour, and broader more 

 dentate and venose final segments. Usually the segments are cut into shallow lobes which are again 

 dentate, and the teeth are carried quite round the margins, as in nigrescens, a feature characteristic of 

 both these species as distinguished from repens. In large specimens the surface is slightly rough at 

 the base of the stipes, but not actually asperous. 



2. II. repens, Presl. — Rootstock pencil-thick free-creeping, scurfy-tomentose ; stipes 2 — 5 ft. I. 

 channelled, stramineous, or darker with a reddish or dark-brown tinge, prickly, puberulous or glandulose 

 villose beneath ; fronds ample, nearly deltoid, tri-or quadri-pinnate, 2-5 ft. 1. about the same w. at the 

 base, chartaceous, green, paler beneath, naked or ciliate, sometimes glandulose beneath rachis and costae 

 more or less asperous, brown or stramineous, glandulose-pubescent ; pinnae sub-opposite, the lower 

 \\ — 3 ft. 1. \ — \\ ft. w. or more, broader usually on the inferior side ; pinnulae generally sub-distant, 

 lanceolate or oblong-lanceolate ; ultimate segments oblong rounded at the top, faintly or deeply lobed 

 3 — 6 li. 1. 1 — 2 li. w. the lobes faintly serrulate ; sori in the hollows of the lobes or lateral teeth ; in- 

 volucres scale-like, pale, cordate.— Hook. Sp. Fil. Vol. 2. t. 90. B ; Plum. Fil. t. 12. 



Var. inermis, Hook. — Stipes and rachises devoid of prickles, bright, or of a clear straw green, 

 and nearly or quite naked. 



Var. II. hostilis, Presl. — Fronds as large, but cutting finer; final segments 1-1^ li. 1. \-% li. w. — 

 Hooker and Baker, Syn. Fil. p. 130. 



Plentiful and widely spread from 2000-6000 ft. alt. on the skirts of forests, open banks, and in 

 coffee fields. Varying greatly in prickliness and vestiture, one form being densely aculeate nearly 

 to the top of the rachis and on the lower part of the costao, and also pubescent and glandulose, and 

 very sticky when fresh ; others being only slightly armed, or like the var. inermis not at all, and 



