TAB. XC. 
Acrostichum (Elaphoglossum) DIMORPHUM, Hk et Gr. 
Caudice horizontal! vel ascendente crassiusculo radicante 
apice imbricatim paleaceo, stipitibus copiosis approximate 
4 uncias ad spithauuearn longis subrobustis per tot am lon- 
gitudinem sparse paleaceo-squamosis, frondibus sterilibus 
3-4-uncialibus oblongo-lanceolatis costatis obtusis coriaceo- 
membranaceis margine lobato-pinuatifidis junioribus minute 
squamulosis, venis oblique pateutibus, costis subtus deci- 
duo-squamulosis, fertilibus paulo minoribus subintegerrimia 
vel siuuato-lobulatis dorso (ut videtur) toto capsuliferis. 
Acrostichum dimorphum, Hook, et Grev. Ic. Fil Tab. 145, 
frons fertilis inclusa, (not “ exclusaf Fee). Fee, Hist, des 
Acrost. p. 40. 
Olfersia dimorpha, Pr. Tent. Pterul. p. 235. 
Elaphoglossum dimorphum, Moore. 
Hab. St. Helena, on rooks and walls, Genl. Walker, Dr. 
Sh liter (who also sent specimens from Madras, but they 
were probably taken out thither from St. Helena) ; top of 
Diana’s Peak, very common, Dr. Hooker. 
This and the subject of our following plate, Acrost. (Ela- 
phoglossum) bifurcation are very remarkable plants ; peculiar 
to tire island of St. Helena; and, as Dr. Hooker assures 
us, growing apart from each other ; and, where he has seen 
them, exhibiting no appearance of being forms of one and 
the same species. Nevertheless, M. Fee, who does not admit, 
in his Histoire des Acrostichees, the A. furcatum, observes 
at p. 40. under Acrostichum dimorphum, Hook., “cette espece 
est parfaitement tranchde, et la dissimilitude des feudles ne 
permettra pas de la meconnaitre. ’ He goes on to say “ l A bi- 
furcatum pourrait bien n’ etre autre chose q une forme tres- 
divisee de VA. dimorphum .” Presl, having in the interim 
established his genus Microstaphyla, with no character except 
form, that I can see, to distinguish it from Elaphoglossum (his 
Ofersia) ; (“ sorus,” he says “ acrostichoideus”), founded on a 
solitary species, the Acrost. bifurcatum, Sw., M. Fee in his 
7me “Mem. sur les Fougeres,” adopts the Genus, repeats his 
views respecting the oneness of Her. dimorphum and Her. 
bifurcatum , and asserts that our figure of the former “ peche 
par l’exactitude, la fronde fertile figuree n’appertenant pas 
vraisemblablement aux frondes steriles.” He describes and 
represents the sori of Microstaphyla as “ nervilluires ,” which 
we cannot confirm by our specimens. TV e must refer our 
readers to the next following description for further obser- 
vations on these two Ferns. 
Tab. XC. Fertile and sterile fronds of Acrostichum (Ela- 
phoglossum) dimorphum, Hook, and Grev. ; natural size. 
Fig. 1. Portion of a sterile, and f. 2. portion of a fertile 
frond ; magnified. 
Cent. 2. t. 90, 
