Plantae cubenses Ekman. III 403 
„The ‘mogotes’ are a series of limestone mountains of Jurassie 
age, very steep and rough, beginning near Mendoza in western Pinar 
del Rio and extending over Guane, Luis Lazo, Sumidero, Vifales, 
Pueblo Palma to Pan de Guajaibön and San Diego de los Bafios. They 
do not form a continuous range, but rather groups divided by pine- 
lands, and may ever occur completely isolated. In each group several 
mountains may be isolated from the rest by flat rather fertile valleys. 
There are three groups of real mogotes: Luis Lazo-Sumidero, Vifiales 
and Las Guacamayas (near Pueblo Palma). The little-known Sierra de 
la Güina (near San Diego de los Bafios) is also a mogote and even the 
famous Pan de Guajaibön must be considered one on account of its 
habitus and its flora, although geographically belonging to Sierra de 
los Organos, group of Rosario. The flora of the mogotes is very dif- 
ferent from that of other limestone mountains in Cuba. Lots of species 
occur only here. Some of them may be found in all ‚mogotes, some 
have only a local distribution. A few species common in mogotes may 
be found f. inst. in the limestone cliffs of Rio Taco-taco and Santa Cruz 
and some even in Prov. Habana, in the hills of Camoa and Tapaste. 
The species of the mogotes show relationship with those of limestome 
mountains in eastern Mexico. One could imagine, that this peculiar 
flora of the mogotes would go parallel that of the pinelands of Pinar 
del Rio, but the connections of these floristical formations point in 
different direction, that of the mogotes, as already mentioned, to Eastern 
Mexico and Texas, and that of the pinelands to Trinidad and Vene- 
zuela, as well as to Florida.* 
Ueber seine Ansicht, betreffend die geologische Entwickelung des 
jetzigen Cuba theilt mir Herr Dr. Exman im Briefe vom 22. März 1923 
das folgende mit: „I might tell you about the conclusions one might 
draw as to the isolation of the different mountains in Cuba judging 
from their flora.. Cuba once was separated in four islands or island 
groups, namely Pinar del Rio, Santa Clara, Sierra Maestra and Sagua- 
Baracoa (inel. Sierra de Nipe, Sierra Cristal and the Baracoa mountains 
as subdivisions). Rather early was Pinar del Rio united with Santa 
Clara and the upheavel went as far as to Holguin, where quite a 
number of western plants are to be found. The lowlands between 
Antilla-Banes in the north to Manzanillo in the south were apparently 
the last ones to emerge out of the tertiarian sea. This country is still 
‘sally’ and coastal plants may be found far inland. It is not neces- 
sary, however, to explain isolation of mountain groups by previous 
submersion of the intervening plains, as mountain plants cannot pos- 
sibly spread over plain country. Tropical forests bar the mountain 
flora as well as the sea would.“ 
26* 
