NOTEWORTHY LEJEUNEAE FROM FLORIDA 
serving as organs of vegetative reproduction. Such leaves and 
branches are unknown in Brachiolejeunea but are found in the South 
American P. torulosus (Lehm. & Lindenb.) Trevis.,^ as understood 
by Spruce, although their true significance has been overlooked. 
Vegetative reproduction by means of leaves which become sepa- 
rated and which afterwards give rise to new shoots by a process of 
regeneration are now known in several genera of the Hepaticae, In 
most cases the deciduous leaves are essentially like ordinary leaves and 
the line of separation is irregular. Such leaves are " Bruchblatter," 
according to the definition of Correns.^ In rarer cases the leaves are 
distinctly modified and separate by means of a regular and definite 
line. Such leaves are " Brutblatter." Examples of the latter have 
been described by the writer in Rectolejeunea flagelUformis Evans and 
R. Berteroana (Gottsche) Evans,' and their occurrence has been noted 
in Frullania Bolanderi Aust.^ 
The caducous leaves of Ptychocoleus heterophyllus are likewise 
Brutblatter. Although they show the usual differentiation into lobe 
and lobule, both are greatly reduced in size, the lobe measuring about 
0.25x0.2 mm. and the lobule 0.14x0.09 mm. The latter is further 
distinguished by bearing only one or two marginal teeth, not inflexed 
as on ordinary leaves. The separation takes place at the very base 
and no cells are torn across in the process. After separation the basal 
cells project as minute crenulations. 
The branches which bear the caducous leaves vary greatly in 
length but their growth is limited sooner or later, and no evidence is 
at hand that they ever revert to the typical vegetative condition. In 
one case thirty pairs of leaves had been produced. The transition 
between ordinary leaves and caducous leaves is abrupt; as soon as 
the latter begin to be formed the branch curves away from the sub- 
stratum and ceases to form rhizoids. The persistent underleaves are 
much like ordinary underleaves and their reduction in size is less 
marked than in the case of the leaves. They are very densely crowded, 
however, and are distinguished also by being squarrose and more or 
Mn his Species Hepaticarum (5: 37. 1912) Stephani cites the present writer 
as authority for this combination with the reference, "Torr, Bot. CI., 1908, p. 165." 
If this reference is consulted it will be seen that the combination is correctly assigned 
to Trevisan. 
^ Unters. iiber die Vermehrung der Laubm. 338. 1899. 
^ Bull. Torrey Club 33: 10, 13. 1906. 
^ Bryologist 18: 88. 1915. • 
