BB 
Liebm. Knowing how exact MrTrenius was in his determinations I do not hesitate 
to call the present species D. equestris, although Kunze described the coste as being 
»bullato-squamose« beneath, which, as I understand the term, is not the case in 
any form referred hereto by me; still the scales are often rather vaulted, and KuNZE 
has perhaps called such scales »bullate«. 
D. equestris is a critical and variable species, closely related to D. ampla, and 
it is not always easy to distinguish it from that species, which, as far I know, does 
not occur in Mexico. The form that I consider typical differs from D. ampla_ by 
its lamina being vivid green to dark green and by the scales. The basal scales 
form a generally smaller tuft than in D. ampla and are of a darker colour, reddish 
brown or nearly castaneous; those of the stipe, rachis and coste are less numerous, 
often few, ovate-lanceolate or ovate, rarely bright brown, as a rule lurid-brown with 
paler edges; scales of the midribs of secondary pinn beneath divaricating, broadly 
ovate or ovate-lanceolate, shortly acuminate, lurid-brown, glossy, often iridescent 
(Fig. 10 c). Upper surface with Ctenitis-hairs along midribs and veins and edges, 
not glandulose, underside somewhat glanduloso-pubescent on the midribs, with age 
glabrous. In cutting some forms scarcely differ from D. ampla, still the secondary 
pinnules are, as a rule, more oblique and somewhat upcurved, the tertiary segments 
of larger specimens are acute and deeply lobed with falcate lobes. Sori commonly 
confined to the lower two-thirds of the larger pinne, rather small, often red-brown. 
Indusia deciduous, reddish, glandular, ciliate. 
D. equestris is a most variable species, if really all the specimens referred to 
it rightly belong here. In some specimens the indusia are subpersistent, f. inst. 
L. ciliata Liebm., in others I have not found a trace of an indusium (P. alsophiloides 
Liebm.), but atheviitse indusiate and exindusiate forms are perfectly similar, and I 
have not succeeded in finding any other constant character by which they were to 
be distinguished from each other. A. Bourgei Fourn., with which <A. scabriusculum 
Day. is identical, is a form with more remote, shorter and broader, ovate-oblong 
secondary pinnule; it is very large, the basal pinnez nearly 50 cm long. 
Mexico. Vera Cruz: S. Antonio Huatusco, LiepMANN nr. 2394 (H = Lastrea ciliata Liebm.); Vallée de 
Cordova, BourGEAU nr. eg 1838 (B, S, W), 1839 (H, RB= A. Bourgei' Fourn.), 2172 (H, RB), 
r. 59, 61, 141a (W), C. R. Orncurr nr. 3214 (W); Ravines above Orizaba, gee nr. 
6132 as pas RB, 5, oo scabriusculum Day.); Zahuapan, C. A. Purpus nr. 2932, 4253 (W). 
— QOajaca: Trapiche de la Concepcion, LIEBMANN nr. 2406 (B, H = Pol. nope Cnet, 
Conzatti nr. 728 (RB) — MicHoacan: Falls of Fzararacua Uruapan, PRINGLE nor. 7 
Tepic: E. Patmer nr. 1951 (W); Pedro ch J. N. Rose nr. 3327 
Guatemala, Dept. Solola: Santa Barbara, W. C. SHANNON ed. J. D. S. nr. 249 pt. (W) — Dept. 
Zacatepequez: San Rafael, DONNELL ae nr. 2731 (W)! Volcan Sepa DonNELL SMITH 
nr. 2739 (W), W. A. KELLERMANN nr. 5242 (W) — Dept. Quiché: Miguel Uspantan, HEYDE 
et Lux ed. J. D, S, nr, 3250 (W) — Dept. Santa Rosa: Volcan Tacoepenke HEypE et Lux ed. 
J. D. S. nr. 4425 (W) — Vicinity of Cacao, H. S. Barser nr. 173 (W) — All specimens of the 
DonNELL SmitH collection were distributed as Nephrodium amplum Baker. 
