2 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 
species it will stand nearest to A. montanum.” From which it may 
be noted that Doctor Underwood was not only unwilling, apparently, 
to ascribe to A. adiantum-nigrum itself an extra-Kuropean range 
(though the species is usually accredited also to various parts of 
Africa, and to the Himalayas, Asia Minor, and other parts of Asia), 
but that also, in accordance with his often-expressed views as to the 
relatively restricted range of fern species, he was inclined upon @ 
priori grounds to look upon the American plant as specifically distinct 
from that of the Old World. That A. adiantum-nigrum as ordina- 
rily accepted does occur in Africa and Asia is apparent from speci- 
mens at hand; and if we admit the various forms distinguished by 
Milde,' Luerrsen,? Christ,? and others as constituting but a single 
highly variable species, there seems to be no logical ground for re- 
garding A.andrewsii as other than a geographical phase of A. adian- 
tum-mgrum. Excepting only Athyrium filizx-foemina, there is, prob- 
ably, no fern occurring in the United States which closely approaches 
it in extent of variation. 
The two illustrations (Pls. 1 and 2) herewith represent at natural 
size the type specimens of Asplenium andrewsti, which have courteously 
been lent from the Rocky Mountain Herbarium, University of Wyo- 
ming, by ProfessorAven Nelson. Ingeneral shape the laminais appar- 
ently unusual for A. adiantum-nigrum in its relatively great width. 
Most of the foreign material at hand most closely resembling this 
shows blades elongate-deltoid in form, the upper portion often atten- 
uate,—a leaf shape more nearly approached by some of the smaller 
fronds here shown. In fact not one frond of the foreign material 
available for comparison has precisely the same leaf shape as that 
of A. andrewsii, the nearest approach being in specimens from Doul- 
lens, France, Copineau, July 12, 1887, and from Devonshire, England, 
Ware, July 15, 1904, These appear to represent the variety argutum, 
as described by Luerrsen. Lacking a first-hand knowledge of A. 
adiantum-mgrum as it occurs in Europe, I hesitate to refer to it 
without reservation this American form, which is known only from 
such meager material; but I believe that the highly complex ‘“‘spe- 
cies’? A. adiantum-nigrum, as generally understood at present, 
embraces among its various and varying forms several elements 
which, in their extreme states, differ more widely from each other 
than from A. andrewsii. In degree of dissection, leaf texture, color 
of leaf tissue and of vascular parts, shape of pinne, extent and char- 
acter of soriation, and in more minute characters, such as the pecul- 
iar form and structure of the long, slender, hair-pointed scales of the 
rhizome, the American plant certainly agrees very closely with some 
1 Milde, Fil. Eur. Atlant. 85. 1867. 
? Luerrsen, Die Farnpflanzen 260. 1889. 
3 Christ, Die Farnkriiuter der Schweiz 68. 1900. 
