164  LEJEUNEAE OF THE UNITED STATES AND CANADA 
its perichaetial bracts. The same peculiarities of the bracts will i 
also serve to separate it from M. bullata, which is a much smaller : 
plant with more erect lobes and relatively larger lobules. It dif- t 
fers from M. lucens in its darker color, in its smaller leaf-cells, and 
in its smaller and differently shaped underleaves. Its underleaves x 
will also distinguish it from M. Ruthii, a larger plant, the leaf-cells 5 
of which are also larger and have slightly thickened walls. Y 
19. Microlejeunea bullata (Tayl.) 
PLATE 21, Fics. 20-29 
Lejeunea bullata Tayl. Lond. Jour. Bot. 5: 398. 1846. 
Lejeunea (Micro-Lejeunea) bullata Spruce, Hep. Amaz. et And. 
289. 1846. 3 
Pale or bright green, scattered or loosely depressed-caespitose: 
stems prostrate, closely appressed to substratum, 0.03 mm. I 
diameter, sparingly and irregularly branched, the branches widely | 
spreading : rhizoids scanty: leaves distant, the lobe erect OF — 
slightly spreading, ovate, 0.17 mm. long, 0.1 mm. wide, rounded = 
to obtuse at the apex, margin entire or subcrenulate from project- - 
ing cells, antical margin variable, sometimes arching across axis ' 
and rounded at base, sometimes almost straight and reaching just x 
beyond edge, postical margin forming a continuous line with keel; on 
lobule strongly inflated, ovoid, 0.14 mm. long, 0.08, mm. wide, - 
keel strongly arched, free margin entire, plane or usually involute : 
to apex, then obliquely lunulate to end of keel, apex tipped uk 
a single, straight or outwardly curved projecting cell; cells of lobe | 
more or less convex, thin-walled throughout or sometimes W 
very minute trigones, averaging 12 p in diameter: underleaves 
distant, ovate to orbicular, 0.06 mm. 1 ng, 0.05 mm. wide, nar” 
lobes, three to five cells long, two cells wide at base and ending M 
a row of two cells, margin entire: inflorescence dioicous: 2 IM 
florescence on a leading branch with a single, sterile and simple | 
innovation ; bracts complicate, subequally bifid, the keel wingless 
or with a narrow, crenulate wing, lobe obliquely spreading, oblong, 
tooth near apex ; bracteole slightly connate on both sides, oblong, 
0.3 mm. long, 0.15 mm. wide, bifid about two fifths, sinus variable, 
