DISTRIBUTION OF LIVERWORTS. 285 
Considering the proximity of our Southern region to the tropics, 
where these plants attain such a high development, the small number 
of forms which are held in common with tropical America, and which, 
on this contipvent, are not found outside of warmer temperate regions, 
such as Dumortiera, Reboulia, and Sphaerocarpus, is remarkable. 
Most of the genera represented in greatest numbers in the cooler tem- 
perate region (Alleghenian area), and more or less of a cosmopolitan 
distribution, are met with in every part of the State—for example, Ric- 
cia, Ricciella, Marchantia, Riceardia, Cephalozia, Plagiochila, Porella, 
Scapania, Lejeunea, Frullania, and others. There can be little doubt 
that some of the genera prevailing in the Northern States and Canada, 
not yet known from Alabama, will be added to our flora by a closer 
search for the plants in the Mountain region. 
About one-half of the species known from Alabama belong strictly 
to Eastern North America; 14 species are held in common with 
Europe, and 11 occur on the Pacific slope, mostly in its northern exten- 
sion, all of which, with the exception of Asterella tenella, are also widely 
distributed in the cooler temperate zone of Europe. 
Little more than one-half of the liverworts so far reported from the 
State are of a decided Southern distribution. Strictly confined to the 
subtropical district (Louisianian life area) are the following: 
Marchantia disjuncta. 
Sphaerocarpus terrestris. 
Fossombronia faveolata. 
Plagiochila ludoviciana. 
Cephalozia media (?). 
Phragmidium xanthocarpa. 
Lejeunea austini. 
Lejeunea mohrii. 
Lejeunea auriculata. 
Frullania kunzei. 
Frullania caroliniana. 
Frullania donnellii. 
Anthoceros carolinianus. 
Anthoceros ravenelii. 
The following are confined within the warmer temperate zone (Caro- 
linian life area): 
Riccia lamellosa. 
Reboulia hemispherica. 
Dumortiera hirsuta. 
Pallavicinia lyetlii. 
Fossombronia angulosa. 
Plagiochila undata. 
Cephalozia virginica. 
Bazzania trilobata. 
Phragmicoma clypeata. 
Lejeunea serpyllifolia. 
Frullania squarrosa. 
The species extending to the cooler temperate and frigid regions are 
scattered over the State from the Gulf shore to its northern limit. 
The specimens early collected by the writer were identified by the 
late Mr. C. F. Austin. His collections of later years have been exam- 
ined by Professor Underwood, to whom thanks are due for this, as also 
for his assistance in revising the list of Hepaticae from Alabama. 
