Evans: HeEpaticaE OF Puerto Rico 27 
unusually long and sometimes measures four or five cells across, 
while the apical tooth, consisting of a single cell, can usually be 
demonstrated without dissection. Although the structure of this 
lobule is essentially the same as in Z. Sagracana, it is markedly 
different in appearance and shows no indication of the hemispher- 
ical basal swelling which has been described for that species. The 
underleaves of L. subfusca are distant and broadly orbicular, meas- 
uring 0.25 x 0.3 mm. The differential characters derived from 
the bracts have already been indicated by Schiffner and afford 
another reason why the two species should be kept apart. 
In the Synopsis Hepaticarum a specimen of Lejeunea subfusca 
is quoted which was collected in Chile by Bertero. <A portion of 
this specimen, also sent by Count Solms, has been studied by the 
writer and is evidently distinct from the Javan specimen. In all 
probability it represents a slender and sterile form of Z. Sagraeana 
but is too fragmentary for positive determination. Many years 
later Lejeunea subfusca was doubtfully reported from Brazil by 
Spruce * and from Juan Fernandez by Mitten.¢ Since both of 
these records are considered untrustworthy, even by their authors, 
there seems to be no good reason for regarding the species as an 
American plant. 
Several varieties of Z. Sagraeana have been described. Some 
of these are based on differences in the size and form of the lobule, 
Some on differences in habit. Whether these differences are con- 
stant or simply due to environmental conditions can hardly be de- 
termined at the present time. Slender and poorly developed forms 
when sterile sometimes resemble the: following species so closely 
that it is impossible to determine them with certainty. 
LopHOLEyEUNEA MUELLERIANA (Gottsche) Schiffn. 
Lejeunea Muelleriana Gottsche, Mex. Leverm. 184. 1863. 
Lejeunea (Lopho-Lejeunea) Muelleriana Spruce, Hep. Amaz. et 
And. 121, 1884. 
Lopholejeunea Muelleriana Schiffn. Bot. Jahrb. 23: 599. 1897. 
: rownish-green, usually paler and less robust than the preced- 
Ng species, somewhat glossy, growing in depressed mats: stems 
“gt i a ak ale 
*Hep. Amaz. et And. 122, 1884. 
T Challenger Rept. Bot. 13: 88, 1884. 
