Evans: HepaticAE OF PuERTO Rico 29 
inflorescence dioicous: @ inflorescence unknown: ¢ inflorescence 
terminal on a short or somewhat elongated branch; bracts in one 
to four pairs, closely imbricated and strongly inflated, the lobe 
obliquely spreading, acute, lobule acute, tipped with a small 
straight apical tooth separated from the end of the keel by a shal- 
low and subacute sinus : antheridia borne singly (/. 3, f. 7-8). 
On living leaves. El Yunque, Zvans (23 7..). 
The underleaves of D. dissitifolia are more complex than in 
any of the other Puerto Rico species and form one of its most 
striking peculiarities. They show their complexity in the large 
number of cells of which they are composed, the widely spreading 
divisions and the marginal portion of the base both showing more 
than the usual number. These complex underleaves to be sure 
are not invariably developed, those on slender axes often showing 
a smaller number of cells than those on robust axes. 
D. dissitifolia is only a trifle larger than D. Araucariae which 
it much resembles in habit. The latter species differs in its dis- 
tinctly denticulate leaves, in its ocelli, and in the abruptly pointed 
lobes of its perigonial bracts. J. dissttifolia also resembles to a 
certain extent D. dioce/lata with which the type-specimens are 
badly mixed. D. diocellata, however, is a more robust plant with 
broader and blunter ocellate leaves and differs further in the thick- 
ened walls of its leaf-cells and in its diandrous perigonial bracts. 
The propagula of D. dissttifolia are borne on branches which 
are scarcely modified and are frequent both on male and on sterile 
individuals. In several cases a propagulum which had become 
established developed a few normal leaves and then passed directly 
into a male inflorescence without branching. The first leaves and 
underleaves of the propagula are less specialized than in Leffo- 
lejeunea, the disc on the first underleaf being small and the second 
leaf showing a well-developed lobule. In the first few leaves, how- 
ever, the lobe remains short, extending but slightly beyond the 
lobule and its postical margin frequently bears from one to three 
sharp teeth. 
Drepanolejeunea bidens (Steph.) 
Lejeunea (Drepano-Lejeunea) bidens Steph. Hedwigia, 29: 71. 
1890. 
Yellowish-green, growing in thin and loose patches: stems 
0.035 mm. in diameter, prostrate, irregularly pinnate, the branches 
