166 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 
to 10 cilia on the edges of the dorsal suture; longest leaves 1.5 mm. long, 0.3 
mm, wide at the base; cilia 0.045 to 0.076 mm. long; sets deciduous, up to 1 mm. 
long, 0.034 to 0.068 mm. thick, white, spinulose-roughened. 
Spikes terminal, nearly quadrangular, up to 2 cm. long, 1 mm. thick; sporo- 
phylls 1.75 mm. long, 1 mm. wide, deltoid, auriculate at base, narrowly sulcate 
dorsally in a median line up to the ciliate setigerous apex, 15 to 25-ciliate on 
the margins, occasionally very minutely ciliate on the base, with 4 to 10 cilia 
on-the edges of the dorsal suture; sets and cilia similar to those of stem leaves; 
auricles rounded-deltoid, 0.2 mm. wide. 
Megasporangia reddish yellow, 0.7 mm. in widest diameter; megaspores crus- 
taceous, whitish, more or less minutely punctate, rougher on the commissural 
side, 0.3 to 0.85 mm. in diameter; microsporangia 0.6 mm. in widest diameter, 
reniform, orange or brownish orange; microspores abundant, bright orange, 
0.03 mm. in diameter. 
Type in the U. 8. National Herbarium, no, 2282938, collected in the vicinity of 
Eustis, Lake County, Florida, July 16-31, 1894, by George V. Nash (no, 1449). 
Other collections of this species are: 
Frorma: Dry sandy soil, Lake County, Nash 1449 (G,M,Y). Sanford, 
Orange County, September, 1900, Rapp (N). Sandy pine woods, Ala- 
pattah, Dade County, Haton (N, G). 
DISTRIBUTION: Central and southern Florida. 
Selaginella humifusa, which is the species confused by Underwood with his 
S. arenicola, differs markedly from that species in several respects. Whereas 
the leaves of each are of nearly the same length on the inner surface from the 
point of attachment to the tip, the long basal portion of the leaves of S. areni- 
cola makes them appear on the outer face or dorsal side from half as long 
again to twice as long as those of 8. humifusa. The basal portion of the leaves 
of S. humifusa may or may not have a few very minute cilia upon it, but this 
portion of the leaves of S. arenicola usually has a distinct clump of cilia quite 
as long as the marginal ones. Selaginella humifusa has cilia along the edges 
of the dorsal suture, and S. arenicola never has them. It must be borne in mind, 
however, that these cilia are, like the marginal ones and the sets, more or less 
deciduous, and are not to be found on every leaf. The leaves of 8S. humifusa 
are apparently 8 to 10-ranked and those of S. arenicola apparently never more 
than 6-ranked. The latter species is less loosely tufted than the former, as 
also much more slender. 
This species differs from its closest ally, S. funiformis, in the following char- 
acters: The leaves are thinner and flatter, not so closely appressed, and (in 
drying) of a much lighter green color. The dorsal cilia are large and rather 
abundant in S. humifusa and exceedingly minute or absent in S. funiformis. 
The spores of the latter are much rougher than those of S. humifusa. The stiff, 
cordlike appearance of S. funiformis furnishes a rather obvious distinguishing 
character, as opposed to the softer and more lax appearance of S. humifusa. 
EXPLANATION OF PLATB 18,.—Type specimen of Selaginella humifusa. Natural size. 
4, Selaginella funiformis Van Eseltine, Proc. Biol. Soc. Washington 30: 161, 
1917. PLATE 19. Figure 66. 
Plants erect, cespitose, rigid, up to 12 cm. high; rhizophores abundant at the 
base of shoots, sparse along the older portions of the stem; stems (including 
leaves) up to 1.2 mm. thick, rigid, sparsely branched at intervals of 7 to 10 mm., 
primary branches few, 5 to 8 cm. long, these bearing few secondary branches 
(up to 20 mm. long); ultimate branchlets occurring throughout, up to 5 mm. 
long, simple, closely ascending; leaves 8 to 12-ranked, very closely appressed, 
imbricate, in the younger stages olive-green, in age becoming dull brown, thick- 
