approved. His characters will therefore generally be adopted, 
with perhaps some slight modifications. We follow him in 
placing the plant in the genus d//osorus, though it is difficult to 
express in words how it differs from Péeris; and with him it 
includes plants differing much in habit. 
Allosorus cordatus is a native of Mexico and New Grenada: 
nearly allied to Allosorus fleeuosus (Kaulf., Pteris, Zink, et Hook. 
Ic. Pl. Rar. t. 119, but that is a climbing plant), and still more 
so to A. sagittatus, Presl, in Schkuhr, Fil. Suppl. t. xxiv. ; nor 
are we sure that the last is specifically distinct. Our figure 
is taken from fertile plants in a cool greenhouse of the Royal 
Garden, December, 1852, where they were reared from seed 
in 1842. 
Descr. Rhizoma short, creeping, almost as thick as one’s little 
finger, if we include the closely imbricated subulate scales with 
‘ which it is densely clothed. Stipites aggregated, stout, from six 
inches to nearly a foot long, straw-coloured, clothed for a good 
part of the way from the base with numerous pale-coloured, 
scattered, subulate, chaffy scales. Main rachis straight, stout, 
and, as well as the slightly flexuose, slender partial rachises, of 
the same colour as the stipes. Frond almost a foot long when 
fully developed, oblong-ovate in circumscription, bipinnate, more 
rarely below tripinnate. Pinaules coriaceous, downy or more 
or less hairy, those on the upper side, towards the margin, glan- 
dular, ovato-cordate, the base unequal, nearly sessile, obtuse, ge- 
nerally all fertile, penniveined, the veins compact, two or three or 
more times forked. ‘The margins much reflexed, and somewhat 
membranous at the edge, and thus constituting the continuous 
involucre covering the sori. 
Fig. 1. Pinnule:—magnified. 2. Portion of the same —more magnified. 
