Evans : Hepaticae of Puerto Rico 15 



cell-walls. The ocelli, however, which form a characteristic feature 

 of R. Berteroana, are either indistinct in the present species or else 

 are wholly undeveloped. R. emarginnliflora also fails to develop 

 flagelliform branches, but these are replaced to a certain extent by- 

 ordinary leafy branches with scattered leaves. These leaves, which 

 are scarcely or not at all modified, secure vegetative reproduction 

 for the species in the same way that the crowded elobulate leaves 



fiagellift 



They easily become 



separated from the axis, usually carrying their lobules with them, 

 and attach themselves to the substratum by means of scattered 

 marginal rhizoids. When this is accomplished each leaf gives rise 

 to one or more leafy shoots, sometimes with the interpolation of a 

 thalloid protonema, sometimes directly from the leaf-cells (figures 

 7, 8). In the majority of cases the new shoots or their protone- 

 mata arise from marginal cells. It often happens that a branch 

 loses many or all of its leaves in this way for a considerable dis- 

 tance and thereby acquires a peculiar appearance (figure 3), very 

 different, however, from what is found in the flagelliform branches 

 of the allied species. It approaches in this respect the following : 



* 



Rectolejeunea phyllobola (Nees & Mont.) * 



Lejennea phyllobola Nees & Mont, in Ramon de la Sagra, Hist. 

 Fis. Pol. y Natur. Cuba 9: 281. 1845. 



On bark of trees. Puerto Rico, without definite locality, 

 Underwood & Griggs (8pj). Widely distributed in the West 

 Indies ; also known from Mexico, Costa Rica and southern Florida. 



R. phyllobola bears a strong resemblance to the three preceding 

 species. It differs from all of them, however, in its much larger 

 leaf-cells, which average 2 1 jj. in diameter in the middle of the lobe, 

 in its complete lack of basal ocelli, and in the narrower divisions of 

 its underleaves. The free margin of its lobule is involute to or just 

 beyond the apex, and the apical tooth is distinguished by being 

 short, blunt, and straight. The present species also develops 

 branches with deciduous leaves, but these are scattered as on 

 ordinary branches and no more modified than in R. etnarginuliflora. 

 Unfortunately the lobules in R. phyllobola are often poorly de- 



* For a full description of this species, with synonymy and figures, see Evans, Mem. 

 Torrey Club 8 : 143. //. 20, f. 1-13. 1902. 



