The Anatomy of Matonia sarmentosa, Baker. 299 
THE ANATOMY OF MATONIA SARMENTOSA, BAKER. 
By R. H. Compton, B.A., 
Frank Smart Student of Gonville and Cains College, Cambridge. 
[With Text-Figs. 38—43J. 
rnHE genus Matonia was founded by Robert Brown in 1830 for 
the reception of the single species M. pectinata (Wallich, 13). 
The genus remained monotypic until 1887, when Mr. Charles Hose 
discovered in Sarawak a new species which was later described by 
Mr. J. G. Baker as Matonia sarmentosa (1, p. 256). In 1891, Baker 
figured a portion of the frond, sorus and indusium of the new 
species (2, p. 191 and pi. XIV.). Christ in 1897 gave a sketch of a 
portion of a pinna with his diagnosis (4, p. 337). The most com¬ 
plete description of external features, with notes on the morphology 
of the frond, is that of Diels (6, p. 343). In 1908 Copeland (5, p. 
344) separated the species from the genus Matonia and placed it in 
a new genus Phanerosorus, “ ob rhachin frondissympodialem, pinnas 
dichotomas, et soros haud ad anastomoses venularium pluriurn 
impositos.” While the habit of the frond is strikingly different 
from that of M. pectinata, it may be doubted whether the distinction 
is of generic importance. The two first characters mentioned by 
Copeland as distinctive are paralleled in M. pectinata. The rachis 
of M. pectinata is constructed on a sympodial pattern, according 
to Mr. Tansley and Miss Lulham, (11, p. 480) by the unequal 
development of the two branches of each successive dichotomy. 
The pinnae of the young plants of M. pectinata are clearly dicho¬ 
tomous, and are of the ligulate form which is characteristic of the 
adult M. sarmentosa. As Tansley and Lulham remark (11, p. 481), 
“ the resemblance of the dichotomously branched strap-shaped 
laminae to those of the young M. pectinata is very striking.” The 
character of the venation supplying the sorus appears to be sharply 
distinct in the two cases; in M. pectinata a reticulum of anasto¬ 
mosing veins underlies the sorus ; in M. sarmentosa the sorus is 
supplied by a single vascular bundle. Professor Seward remarks 
(9, p. 192) that “ as a rule comparisons based on venation characters 
and on the form of the frond are of secondary importance, and in 
some cases practically valueless ; ” and in this instance the dif¬ 
ferences between the fronds of the two ferns are seen to be super- 
