Evans: Hepaticae of Puerto Rico 281 



sometimes rounded but usually minutely apiculate and often bear- 

 ing one or two additional teeth, margin otherwise entire ; lobule 

 always conforming to the normal type, narrowly ovate in outline, 

 strongly inflated, o.i/ mm. long, 0.09 mm, wide, keel more or 

 less arched, slightly roughened from projecting cells, forming an 

 obtuse angle wath the postical margin of the lobe, free margin of 

 lobule straight or nearly so, apical tooth short and slightly curved, 

 hyaline papilla in a slight depression, sinus lunulate ; utriculi fre- 

 quent, occurring singly or in pairs at the base of a branch, some- 

 times attaining a length of 0.65 mm., free lamina strongly concave 

 and forming a cyhndrical canal leading into the sac; cells of lobe 

 averaging 14/^ at the margin, 23/i in the middle, and 40 x 28/i at 

 the base, trigones large and often confluent, triradiate and mostly 

 truncate at the ends of the rays, intermediate thickenings occa- 

 sional, approximately rectangular or quadrate in outline ; ocelli not 

 developed : underleaves distant to slightly imbricated, nearly plane, 

 orbicular, 0.6 mm. long, rounded at the base, bifid about one third 

 with erect, acute or subacute lobes and a narrow sinus, margin 

 entire, rhizoids when present springing from a rudimentary disc : 

 inflorescence dioicous : female branch very variable in length, the 

 flower subtended by a single, short and often floriferous innovation ; 

 bracts complicate, obliquely spreading, the lobe ovate to orbicu- 

 lar-ovate, 0.85 mm. long, 0,6 mm, wide, apex rounded, apiculate 

 or subacute, margin entire or irregularly toothed near the apex, 

 lobule ovate-lanceolate to obovate, 0.55 mm. long, 0.35 mm. wide, 

 rounded to acute at the apex, margin entire or sparingly denticu- 

 late in the upper part ; bracteole somewhat connate on both sides, 

 broadly ovate or oblong, 0.75 mm. long, 0.6 mm. wide, bifid about 

 one third with erect acute lobes and a narrow sinus, margin entire or 

 with a few scattered teeth ; perianth immersed (except the horns), 

 obovoid, I mm. long, 0.6 mm. wide, surface roughened especially 

 along the keels, apex broad and with a short beak, horns nearly 

 half as long as the main body of the perianth (0.3 mm.), cylin- 

 drical or slightly compressed at the blunt apex, smooth, the two 

 postical horns erect, the two lateral erect or somewhat spreading : 

 (^ inflorescence and mature sporophyte not seen. (Plate 19, 

 FIGURES 12-20.) 



On bushes. El Yunque, Evans (pi). 



It is with some hesitation that C, valida is described as new, 

 partly because species are so difficult to define in Ceratolcjciinca^ 

 partly because it is so closely related to the following species. Per- 

 haps its most striking peculiarities are found in the leaf-cells with 

 their extremely thick walls. When these cells are viewed from 

 the surface, especially in a flattened leaf, they present an unusual 



