Evans: HEpATICAE OF PUERTO RICO 539 
fact which Stephani has already emphasized.* It varies not only 
in color and in size but also in some of the structural characters 
derived from the leaves, underleaves and floral organs, characters 
which are usually regarded as more or less constant. To a 
certain extent this variability is indicated in the preceding des- 
cription, but the lobules and underleaves deserve a few words in 
addition. The lobules vary considerably in size, being sometimes 
no longer than the diameter of the axis; they vary more strik- 
ingly, however, in the relative size of the water-sac as compared 
with the plane portion. In extreme cases almost the whole of 
the lobule enters into the formation of the sac, and under 
these circumstances the keel sometimes makes a very acute angle 
with the stem, thus giving the lobule a strong superficial resem- 
blance to the water-sacs in Frudlania. The underleaves vary 
somewhat in outline but are nearly always broader than long. 
They show more marked variation at the base. The margin in 
this region is sometimes straight, meeting the axis at approxim- 
ately a right-angle, but it may be rounded, subcordate or distinctly 
Short-decurrent. It is not unusual to find these various conditions 
on the underleaves of a single stem, and even the two sides of the 
Same underleaf are sometimes very different from each other. The 
perianth yields some of the most constant characters of the species, 
although its outline varies somewhat with age, becoming longer 
as the sporophyte develops. In rare cases the postical surface 
bears a few scattered cilia near the apex, but it is usually smooth. 
SYMBIEZIDIUM GRANULATUM (Nees) Trevis. 
Jungermannia granulata Nees; Martius, FI. Bras. e262. 1533. 
Phragmicoma granulata Nees, Naturg. Europ. Leberm. 3: 248. 
1838. 
Lejeunea granulata Nees; G. L. & N. Syn. Hep. 311. 1845. 
Symbiezium granulatum Tens Mem. Ist. Lomb. III. 4: 403. 
1877. 
Lejeunea (Platy-Lejeunea) taeniopsis Spruce, Hep. Amaz. et And. 
126, 1884, 
Lejeunia (Platylejeunea) granulata Steph. Hedwigia 27: 285. 
1888. 
Pp Platylejeunea granulata Evans, Trans. Conn. Acad. BO Als SO0E 
* Hedwigia 27: 286. 1888. 
