ten 
subfalcate, the margins slightly crenulato-dentate; surfaces 
naked, but the flexuose costulae pubescent above, beneath 
having a few small deciduous, obovate, pale scales in the 
axils formed with the mid-vein ofthe segments; colour above 
light green, beneath greyish ; texture sub-coriaceons; veins 
pellueid, forked in the outer half or third, reaching the edge; 
sori pale, copious, ascending half to two-thirds up the seg- 
ments, inserted just below the forking of the veins; rachis 
sparsely prickly below, quite naked. 
This has the cutting of A. aspera, but contrasts 
with that species by its small, slender habit, many fronds, 
and pale colour in all its parts. Mr. Baker looks upon it as 
a form of aspera, judging from pinnae, but the best 
distinguishing characters are shown by the trunk and stipes. 
These parts of the species of this and allied genera are so 
cumbersome to collectors from their bulk and prickliness, 
that they rarely reach European herbaria; and yet as good 
distinguishing characters are aflorded by them as by the 
fronds. Indeed, the Jamaican tree ferns are as well indi- 
vidualized, and can be asreadily identified, by the characters 
which the trunk alone exhibits as by those shown by the 
fronds alone. 
Adiantum macrophyllum, Sw., var. bipinnatum, 
Baker, MSS.: stipes long; pinnae more numerous than in the 
type and smaller, base of the frond bipinnate; pinnules oblong. 
Adiantum cubense, Hk., var. nanum, Jenman: 
small, delicate, 3 to 6 inches high; lamina 3 inches long; 
segments 4 to 10, with a larger deltoid terminal one, casually 
bipinnate on the left side at the base. 
Asplenium altissimum, Jenman, n.sp.— Caudex 
stout, erect or decumbent, beset with the persistent bases 
of the past stipites; stipites caespitose, few, suberect, 18 to 
24 inches long, dark coloured, not channelled, puberulous 
and warty with dense raised points, dotted below with largish, 
membranous scales; fronds spreading, ovate, 2 io 4 feet 
long, 16 to 24 inches wide; lowest pinnae little or not re- 
duced, bipinnate; pinnae spreading, 12 to 18 inches long, 
5 to 8 inches wide, often bearing bulbils in the axils of the 
upper ones; pr subpetiolate, 3 to 4 inches long, acu- 
 minate, deeply pinnatifid, the lowest pair reduced; segments 
!a to ®), inch long, 2 to 3 lines wide, oblong, the apices 
rounded, entire, toothed, or lobed half-way to the midrib 
texture firm; under surface puberulous; the costae and co- 
stulae slightly scaly, upper glabrous, the eostulae channelled, 
with accessory sharpedged margins; veins pinnate, simple 
or forked, reaching the edge: sori short, close to the midrib, 
| the inferior occasionally double; involucre tumid, membra- 
