708 Aspidium spinulosum and its Varieties. [November, 
My own observations tend to convince me that Swartz’s plant 
is by no means uncommon. Be that as it may, plants are found 
here abundantly enough that exactly conform to Swartz’s descrip- 
tion as given by him in his “ Synopsis Filicum.” 
What then is Aspidium spinulosum Swz.? Swartz says of it, 
“Frondibus bipinnatis, pinnis pinnatifidis pinnatisque, laciniis 
oblongis acutis serrato-spinulosis, fronde ovato-triangularis; rachis 
glabra, stipite paleaceo.” “ Addenda et emendata,” p. 419 to Syn- 
opsis Filicum, 1806. This describes in part nearly all of our 
American forms. Let us analyze the description and see: 
1. Fronds twice-pinnate. This is true in many cases of spinu- 
Josum, and the varieties dilatatum and intermedium. In large and 
highly developed specimens of the two last forms the fronds are 
often thrice-pinnate, and usually appear to be more divided on 
account of the pinnules being more deeply cut; but the uncer- 
tain application of this character to any one particular form ren- 
ders it unreliable as a specific character, or only of secondary 
importance. 
2. Pinnules pinnatifid, segments oblong, acute spinulose-toothed. 
Common to all of the forms, and therefore as unreliable as the 
first character. 
3. Frond triangular-ovate. This more clearly belongs to the 
var. dilatatum than to any other form, although I have had speci- 
mens of intermedium that were broadly triangular in outline, and 
other things corresponding that form might be regarded as 
Swartz’s plant for all there is in the description to the contrary, 
specimens being found commonly enough that are triangular- 
ovate in outline, bipinnate in structure, with smooth rachis and 
pale-brown scales. 
4. Rachis smooth. This is the case with spinulosum and our 
dilatatum, but in intermedium the rachis is usually finely glandu- 
lar. It will be necessary, however, to collect specimens early in 
order to observe this, as the rachis finally becomes smooth. This 
makes it difficult, if not impossible, to decide to which form 
Swartz’s description was applied without knowing when, and in 
what state his plants were collected. 
5. Stipes clothed with pale brown scales. This is the case, more 
centers peculiar to the most Siyay developed forms are not reli- 
> as a ISEI Pamer 
i or less, with all of our forms. The darker scales with blackish a 
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