our plant; and the segments of the pinnules are described and figured as finely serrated; whereas 
in ours they are mostly entire. The specimens of CyatÁea muricata W. in Siebers Collection 
(No. 337.), referred to by Kaulfuss likewise as that plant (Enum. Fil. p. 259.), have a great resem- 
blance in the fronds to ours, but they are more distinctly crenato-serrate; and the caudex is 
described by Plumier as being only about two feet high. Yet, again, if we look to the specific 
character given by Willdenow of the two above-mentioned species, we shall find that they differ 
only in one word; for, whereas in the one (C. aspera) the segments of the pinnules are said to be 
* serrated at the apez," they are in C. muricata stated to be * crenate." In the fronds of the two, as 
hgured by Plumier (TAs. 3 & 4.), a very great similarity may be observed. — Kaulfuss has taken up 
the two species, and, as it appears to us, has made the main difference to depend on the segments of 
the pinnule in C. muricata being soriferous only in the lower half; whereas in C. aspera the fruc- 
tifications extend to the extremities. "What that author means by the term * receptaculo spherico 
bivalvi," which he introduces into the specific character of the latter, we do not know. 
'In regard. to the genus, the involucre is, in our specimens at least, obsolete. "The capsules form 
so compact a body, that they would appear to be held together by some indusium, however fuga- 
cious: yet in the earliest stages of the fructification which our plants will afford, we find no covering 
to the sori; but under the sorus, if that sorus be very carefully removed, we find a small peltate - 
scale, greatly smaller than the sorus, jagged at the margin, and from which the receptacle of cap- 
sules appears to have originated, and which it may have covered in a very young state. 
