350 Boiver.—Studies in the Phytogeny of the Filie ales, VIII. 
1902 near Apolo in Bolivia at a level of 6,000 feet by Mr. R. S. Williams, 
and described by Miss Slosson. 1 Thus the new genus Loxsomopsis 
appears to be widely spread in Central America, a habitat far removed 
from its nearest congener Loxsoma . Small portions of a dry specimen of 
the last-named species, together with photographs, having been most kindly 
sent to me by the officials of the Smithsonian Institution, Washington, B.C., 
I am able to contribute some notes on this interesting Fern from personal 
observation. These, assisted by the description and drawings already 
published by Miss Slosson, may form a basis for further discussion of the 
relations of the genera Loxsoma and Loxsomopsis. 
L. notabilis is a stately Fern of Bracken-like habit, its rather slim 
fronds rising to a height of as much as eight feet : this is a much greater 
height than that of Loxsoma , though the diameter of the rhizome is less. 
The general characters of the leaf resemble those Loxsoma, but with minor 
differences of outline, surface, and vestiture. The sori are constructed on 
the same gradate plan. They are marginal on the ends of anadromic vein- 
branches, and are curved strongly downwards. When ripe the sporangia 
project from the cup-like indusium, owing, as in Loxsoma , to intercalary 
lengthening of the base of the receptacle (Fig. 1). 
The hairs are characteristic. The rhizome is closely invested by stiff 
bristles. The upper part of each is formed of a simple chain of cells. 
Passing downwards, this widens conically towards its base, with numerous 
cell-divisions, both longitudinal and transverse. A turgid insertion is thus 
produced. It is not a flattened scale, but the base of each hair stands out 
from the surface as a pear-shaped boss. The size may vary even in closely 
grouped hairs (Fig. 2). This is essentially what is found also in Loxsoma. 
The lower surface of the lamina, on the other hand, bears numerous soft 
curved hairs without any basal swelling (Fig. 3). 
The rhizome is cylindrical and rather thin, being about 3-5 mm. in 
diameter, which is odd, seeing that the frond is so tall. The cortex is much 
narrower than in Loxsoma , and surrounds a solenostele in all essentials 
resembling that typical example of solenostely. The departure of the 
leaf-trace was not observed, but sections of the rachis above the second pair 
of pinnae show a structure like that observed by Gwynne-Vaughan in 
Loxsoma , 2 It is an undivided meristele, and presumably the leaf-trace itself 
is also undivided. Thus the similarity of the vegetative region of Loxso¬ 
mopsis in form and structure to that of Loxsoma amply bears out the close 
relationship of the two genera recognized by Christ, and indicates for both 
a relatively primitive position. 
This is further established by comparison of the sori as a whole, as 
may be seen from Fig. 1. The elongating receptacle bears the sporangia in 
1 Bull. Torrey Club, vol. xxxix, p. 285, PL XXIII, 1904. 
2 Ann. of Bot., vol. xv, PI. Ill, Figs. 8 and 7 d. 
