•1 



FERNS : SYNOPTICAL LIST— VII. 



Synoptical List, with descriptions, of the Ferns and Fern- Allies of Jamaica, by G. S. Jenman, Superin- 

 tendent, Botanical Gardens, Demerara (continued.) 



Genus IX. Cyathea.Sori hive-shaped, or subglobose, on the back of the veins ; receptacles eleva- 

 ted and comical, generally setiferous, often c eft in two ; sporangia copious, densely ag°re»ated, ob- 

 vate-cuneate ; involucres of two forms : first, dimidiate, cii cumsessile and bowl-shaped, remaining en- 

 tire after maturity ; second hemispherical, or entirely enveloping the sori at first, very thin, becoming 

 at length much ruptured and broken down into irregular parts ; trunk usually tree-like ; fronds as a 

 rule ample ; veins free. 



The larger number of the tree-ferns of Jamaica belong to this genus, which is conspicuously reore- 

 sented in all situations from the lowest to the highest altitudes, as a rule preferring the moist and espe- 

 cially the cool, avoiding the dry and arid regions. The form of the involucre, which is like a sphere 

 cut transversely with even edge, or, in the other case. wQole or broken down irregularly, divides the 

 genus nearly equally. 



a. Involucres cup or bowl-shaped, with even margiu permanently entire. 

 b. Fronds bipinnate only. 



1. C. Nockii, Jenm. 



2. C. pubeseens, Mett. 

 bb. Fronds tripinnatifid. 



3. C. jamaicensis, Jenm. 



4. C. urborea, Smith. 



5. C. elegans, Heward. 



6. C. nigrcscencs, Jenm. 



7. C. coneinna, Jenm. 



8. G Tussacii. Des. 



aa. Involucres hemispherical — that is completely enveloping the sori at first, subsequently broken 

 down irregularly ; very fragile. 

 b. Fronds tripinnatifid. 



9. C. insignis f Eat. 



10. C. gracilis, Griseb. 



11. C. dissolute, Baker. 



12. C. Schanschin, Mart. 



13. C. furfuracea, Baker. 



14. C. monstrablia, Jenm. 

 bb. Cutting uncertain. 



15. C. conquisita, Jenm. 

 16 C. pendula, Jenm 



1. C. Nockii, Jenm. — Stem less than 2 in. thick, only a few inches 1. procumbent and rooting 

 from the under sid«, corrugated; stipites tufted, few or several, erect, not prickly, rusty- tomentose be- 

 neath, above clothed with dark brown scales, the dwindling pinnae reaching to the base ; fronds erect, 

 spreading, plume-like, 2-4 ft. 1. 5-10 in w. subcoriaceous, dark green glossy, the under pale ; rachis 

 gubangular, channelled, rusty- puberulous, and fibrillose with small whitish grey linear scales which ex- 

 tend to the costae ; pinnae spreading, 1-2 in. apait from rib to rib, sessile, fully pinnate, 3 6 in. L f-1^ in. 

 w. serrate-acuminate; segments slightly apart, \-\ in. 1. 1^-2 (or the basal 3) li. w. curved, the ob- 

 liquely acute, and rather mucronate, apex serrate, the inner ones more or less rounded and free at the 

 base, the basal pair largest and lobed or pinnatifid, the outer adnate ; veins generally once forked from 

 the base ; sori inserted at the forking, close along the mid-rib, not reaching the apex ; involucres cup- 

 shaped rather pruinose, the margin often compressed ; receptacles setiferous. 



Common on a limited area of the disintegrated acclivous forest slopes near Vinegar Hill, a short 

 way below the Government Cinchona Plantations, 4,000-5,000 ft. alt., and less abundant just below 

 Belle Vue. the site of the official residences, where Nock and I first found it in 1874-75. A singular 

 species, distinguished locally by the caudex not being arborescent ; and the small size of the fronds. 

 The vestiture resembles somewhat that of C. Tussacii, but is much less dense. In the largest fronds 

 the dwindling pinnae at the base become abortive, passing into linear filiform glands. Where exposed 

 to the sun the fronds are not mor« than 2 ft. 1., very coriaceous, the edges of the segments reflexed. 

 The habit is that of a large Ncphrodium. There is a frond in the Kew Herb., gathered by Wilson, 

 the locality not marked. 



2 C. pubeseens, Mett. — Stem stout, reaching many ft. high, densely tesselated above, rather 

 prickly ; stipites stout and sharply armed, clothed with narrow chesnut scales, the reduced pinna; 

 reaching nearly or quite to the base ; fronds erect or erect-spreading, 6-8 ft. 1. l£-2£ft. w. base taper- 

 ing apex rather acute than acuminate, very coriaceous, upper side crinkly, dull dark green, under- 

 neath pale and rather glaucous ; rachis and costs) dark brown, rusty-puberulous beneath, coated above 

 with rusty adpressed tomentum ; pinnae very numerous, close, horizontal, f -1^ ft. 1. 1^-lf in. w. ser- 

 rate-acuminate, quite sessile, fully pinnate at the base only, but above this pinnatifid almost as deeply : 



