—26— 



found by Wright and distributed without number in his Hepaticae Cubenses, 

 but has not since been collected. It agrees with 7^. Rappii in the following 

 peculiarities: the inflorescence is autoicous; the lobes have the same general 

 form; the lobules present the same type of structure and are relativel}^ large, 

 measuring about 0.2 X 0.18 mm.; the female inflorescence is borne on a leading 

 branch; the bracteole is connate on one side; the perianth shows the same form 

 and a similar distribution of its keels. The Cuban species, however, is distinctly 

 smaller, the lobes of the leaves rarely exceeding a size of 0.4 X 0.3 mm. It is 

 further distinguished by the presence of a distinct group of enlarged and reddish 

 cells at the base of the lobe, the corresponding cells in F. Rappii showing no 

 special differentiation. The stylus in 7^. cohrensis also yields a few differences. 

 On the ordinary leaves, it measures about o.i X 0.04 mm., and is therefore con- 

 siderably larger than in F. Rappii, where it averages about 0.07 X 0.03 mm. On 

 the perichaetial bracts the difference in size is even more apparent, the stylus 

 in F. cohrensis being in the form of a distinct lobe. 



In addition to F. Rappii no fewer than four autoicous species of Trachy- 

 colea are known from the United States, the others being F. inflata, F. saxicola 

 Aust., F. Oakesiana Aust., and F. Catalinae Evans. The first two of these 

 species have a rather wide distribution and represent southern rather than north- 

 ern types, the third has a distinctly northern range, while the fourth is known 

 only from California. In all four the cell structure conforms to the second type 

 described above. In many respects F, inflata is more closely related to F. 

 Rappii than are the other autoicous species. It differs, however, not only in the 

 structure of the cell walls, but also in the size of the cells, which attain a diameter 

 of about 24 n in the middle of the lobe instead of only 16 ix. Explanate lobules 

 are likewise of frequent occurrence in F. inflata, and the perichaetial bracteoles 

 are free from the bracts. In the very similar F. saxicola explanate lobules are 

 still more usual, and the mouth of the perianth is remarkable in being occluded 

 by papillae which grow out from the margin and inner surface. 



Yale University. 



LEUCODONTOPSIS Cardot * 



{Leucodoniopsis R. & C.) 



Elizabeth G. Britton 



In 1893 this genus was founded on specimens collected in Costa Rica by 

 Tonduz {no. 5616) which were described as L. plicata R. & C. and type speci- 

 mens of which they have kindl}^ shared with me, in exchange for some speci- 

 mens collected by me in the Bahamas in 1904. In both cases the specimens are 

 sterile, but propagate by septate gemmae, growing in clusters in the axils of the 



* P. S. Since writing the above, after notifying M. Cardot and sending him 

 specimens of Dr. Small's no. 3227 from Grassy Key, Florida, he informs me 

 that the spelling should be Leucodontopsis, not Leucodoniopsis. 



