Evans : Hepaticae of Puerto Rico 7 



On a log. El Yunque, Evans (161). The species was origin- 

 ally collected by Spruce in the region of the Amazon and has re- 

 cently been collected in southern Florida. 



The deciduous leaves of this interesting species are set free by 

 a tearing across of the lobe near the lobule, sometimes leaving a 

 complete water-sac behind, sometimes tearing away a portion of 

 its wall ; in any case the lobule is left intact (figure 7). The lobes 

 which thus separate play an important part in the vegetative repro- 

 duction of the species. Even before they become detached they 

 are able to produce straight and unbranched rhizoids, which grow 

 out from scattered marginal or submarginal cells. By means of 

 these rhizoids the lobes attach themselves to the substratum and 

 give rise directly to leafy shoots, without the interpolation of any 

 protonemal structures whatever. Each shoot has its origin in a 

 single leaf-cell, and there are usually from one to three shoots de- 

 veloped on each lobe (figure 8). The first leaves on these shoots 

 are very small, both lobe and lobule being extremely rudimentary. 

 As growth proceeds the leaves gradually acquire a more normal 

 appearance, the first parts to develop being the lobule and enough 

 of the lobe to form the water-sac. The underleaves as a rule 

 appear very early, but in some cases their development is post- 

 poned, and several pairs of rudimentary leaves will be found with- 

 out any corresponding underleaves (figure 9). These variations 

 in development are probably caused by differences in light and 

 moisture. 



Apparently the closest ally of C. decidua is C. jamaicensis 

 Steph.,* a species which has not yet been reported except from 

 Jamaica. C. jamaicensis is a more robust plant, larger in all its 

 parts and with much more conspicuous thickenings in its cell- 

 walls. The male inflorescence sometimes forms a long spike with 

 from six to ten pairs of bracts, although it is sometimes much 

 shorter. The leaves in this species show no evidence of being 

 deciduous. C. aneogyna also retains its leaves. It differs from 

 C. decidua in its smaller size and greater delicacy, in its more fal- 

 cate lobes, the postical margin being distinctly rounded, and in its 

 autoicous inflorescence. 



* Hedwigia 34 : 241. 1895. 



