3Q2 Bower . — Studies in the Phytogeny of the Filicales. 
having been referred to Acrostichum , L., Onoclea Lomariopsis (Fee), Sw., 
Chry sodium , Luerss., and Poly do try a , Keys. It will be seen from its 
detailed characters that it is properly placed as a Blechnoid derivative, 
a position which is suggested in the arrangement of Diels (E. & P., i. 4, 
p. 251) and of C. Christensen (Index Filicum, p. xxxvi). It may, indeed, 
be a question whether there is any valid generic distinction. Christ, on the 
other hand, places it under the old generic name of Lomariopsis , Fee, 
in a position relatively remote from Blechnum (Farnkrauter, p. 39). The 
genus Stenochlaena as defined by Christensen includes eleven species, of 
which .S', sorbifolia and palustris are the best known. They are widely 
climbing Ferns, and are characterized by an extraordinary variability 
of leaf-form. In X. sorbifolia a ‘ Pimpinelloid ’ type is found in the lower 
parts of the plant, which may match very perfectly those of B. filiforme. 
But the sterile leaves scattered upon the climbing axes are of a Blechnoid 
type. The fertile leaves are, however, uniform, and resemble those of 
species of Blechnum , except that the soral region is wide, and everted 
at maturity, as in B. filiforme, so as to expose the very numerous sporangia 
spread over its surface. It is in fact a pronounced ‘ Acrostichoid ’ type. 
This species was collected twice in Jamaica, and the details given below are 
derived from that material. 
Some idea of the great plasticity of the sterile leaves of this plant will 
be gained from the drawings of Christ in his Farnkrauter, p. 40. Further 
reference may be made to Karsten’s description under the old name of 
Teratophyllum aculeatum , var. inermis , Mett., of a Moluccan Fern referred 
by Christensen ( 1 . c., p. 632) to Stenochlaena aculeata (Bl.), Kze. (Buit. Ann., 
vol. xii, p. 143, PI. XIV). Here there are two types of sterile leaves in the 
climbing region, one of which corresponds to the ordinary sterile leaves of 
S', sorbifolia , the other is closely appressed to the surface of the support, 
and Karsten ascribes to these leaves a water-collecting function. 
The climbing stem of S', sorbifolia , which has relatively long internodes, 
is rather variable in size (Text-fig. 11, a , b). Where it is appressed to the 
supporting trunk its side is flattened, and the roots are chiefly located there. 
In addition, rhizoid-like hairs may serve as an additional attachment. 
The transverse section appears roughly polygonal, owing to the fact that 
the insertions of the leaves extend as ridges downwards. The stem and 
leaf-bases are covered by a broad band of sclerenchyma, which is, however, 
interrupted here and there by bands of lacunar tissue, as in Pteridium and 
other Ferns (Text-fig. 11). The general construction is obviously a modi- 
fication of the Blechnum-tyy)Z. There is a girdle of meristeles, here of very 
large size in accordance with the climbing habit. The largest is seen to be 
opposite the support. The leaf-gaps have been numbered in Text-fig. 11,0, 
for purposes of reference. Opposite gaps 2 and 4, a root-trace has arisen in 
the usual Blechnoid way. The leaf-traces consist of a variable number of 
