It would be filling our pages unprofitably if I were to give 
a list of the special localities of this very beautiful tropical 
-American Fern, the most beautiful of a very beautiful genus ; 
they are very numerous. But it does behove me to explain 
why I have brought together so many synonyms, and no less 
than three genera, of some of our most able Fern-botanists, of 
what JI cannot but consider, after the most careful investigation, 
not only to be a true Zrichomanes, but all relating to one and the 
same species. I ought to make an exception perhaps in the case 
of the Meuromanes immersum of Dr. Van den Bosch, which I 
have not seen. I have referred it here doubtfully. It is said 
by the learned author, “a reliquis” (meaning the species or 
forms of Neuromanes) “differt statura minore, consistentia frondis 
et structura, soris immersis.”” The chief character here appears 
to be the emmersed sori. I have samples of the common form 
with involucres partially immersed, while others are almost sti- 
pitate on the apex of an excurrent nerve; and a slight modifica- 
tion of cellular structure is common to this as to many other 
species of Ferns, without affecting specific character. 
As regards the genus, Hedwig, the first describer and figurer 
of this species (hence I erred in adopting Humboldt’s and Willde- 
now’s appropriate name of floribundum rather than of pinnatum), 
and all authors who have figured this Fern, have represented the 
secundary transverse veinlets sometimes short and free, and 
sometimes elongated and uniting with the opposite primary vein. 
‘This character Presl considered of so much importance as to re- 
quire the separation of the plants as a genus, and he named it 
Neurophyllum. Dr. Van den Bosch adopts the genus, but properly 
changes the name to Newromanes, there being already a Newro- 
phyllum amongst Umbellifere, and he constitutes two divisions 
or groups,—l, vere venulis spuriis transversalibus reticulatim 
conjuncte ; and 2, “venulis transversalibus nullis.’ This latter 
section includes the Mewrophyllum abruptum, Fée (Tr. Hostman- 
nianum, Kze.); a plant with every character of Zr. pinnatum, 
save the absence of these spurious transverse veinlets; but thus, 
in reality, removing it from Presl’s Neurophyllum itself. With 
great consistency to his principles, Presl constitutes of this another 
genus, “ Odontomanes,’ in his ‘ Epimelize Botanice.’ My own 
numerous specimens have satisfied me that the presence of these 
spurious veinlets, though very general, is by no means to be de- 
pended upon ; all intermediate stages may be seen, from very co- 
pious and evident transverse veinlets, to their entire absence, as 
Hostmann’s Surinam plant, n. 75, New Granada ones from 
Schlim, n. 228, Purdie’s from Santa Martha, French Guiana, 
from Delessert, and specimens from the Bana River, Valley of the 
Amazons, Spruce, ete., all of which are more or less destitute of 
these veinlets. 
