Evans: HEPATICAE OF PuERTO RICO 223 
nearer the outer extremity of the free margin. The hyaline papilla 
occupies the usual position but no proximal tooth is developed. 
The gemmae, which are produced in great abundance, are confined 
to the apical portion of the lobe, but are situated on the lower 
surface as in D. pellucida. 
The development of the gemmae is essentially the same as in 
Cololejeunea and its allies, so that only the most important features 
of the process need be mentioned. The establishment of the 
mother cell of the gemma, the division into quadrants, and the 
greater growth of the apical quadrants take place as described by 
Stevens for Cololejeunea Biddlecomiae (Aust.) Evans.* In the 
same way each apical quadrant proceeds to divide as a two-sided 
apical cell and cuts off two series of segments, the first division 
wall being parallel with the median wall of the gemma. The 
segmentation, however, is carried considerably further, the number 
of segments being usually from seven to ten. It will be remem- 
bered that five is the highest number of segments observed in 
Leptocolea. The gemma shown in TEXT FIGURE 2, B has ten 
F ee ey 
A espe e 2 tplasiolejeunea pellucida; Morce’s Gap, Jamaica, Evans (55). 
gem: mParous leaf, postical view, X 40. B. Gemma, X 300. C. Germinating 
Ma, Postical view X 40. 
ig on the left-hand side and nine on the right-hand side. 
. alle eauent divisions in the segments are largely by periclinal 
8, as 
many as three such walls appearing in some of the older 
* Bull. 
—. 
Torrey Club 37: 366-360. f. r. 1910. 
