20 
Bryophyten. — Pteridophyten. 
American hepaticae, under each of which it becomes necessary to 
reduce to synonymy one or more species usually regarded as valid: 
1. Microlejeunea laetevirens (Nees and Mont.) Evans, comb. nov. 
(Lejeunea laetevirens Nees and Mont.). This is the Lejeunea lucens 
of Taylor (1846), Spruce (1884), and Stephani (1890), the Microlejeunea 
lucens Evans (1902), and Lejeunea glaucophylla Gottsche (1858). The 
type is from Havana, Cuba, and the species occurs in the south- 
eastern United States and in tropical America generally. 
2. Euosmolejeunea clausa (Nees and Mont.) Evans, comb, nov., 
the type of Lejeunea clausa Nees and Mont. (1840) being from 
French Guiana. A comparison of Lejeunea opaca Gottsche (1845) 
with this shows the two to be the same. This species, recently (1902) 
recognized by the author under the name Euosmolejeunea opaca 
(Gottsche) Evans occurs in Florida and Alabama and is also 
widely distributed in tropical America. The synonymy, which in- 
cludes several other specific names, is given in full. 
3. Frullania obcordata Lehm, and Lindenb., 1845 ,(Junger mannia 
obcordata Lehm, and Lindenb., 1834), based on Guianan specimens, 
proves to be identical with Frullania caroliniana Sulliv., 1846, of the 
Southern United States, and must supercede the latter name. F. 
Martiana Gottsche, 1845, is also the same. The species is of wide 
distribution in American tropics. Maxon. 
Dowell, Ph., New ferns described as hybrids in the genus 
Dryopteris. (Bulletin of the Torrey Botanical Club. XXXV. p. 135— 
140. April 20, 1908.) 
As the result of field studies carried on for several years, mainly 
in New Jersey and New York, the author describes the following 
supposed hybrid forms as new: Dryopteris cristata X intermedia, 
D. Clintoniana X intermedia , D. Clintoniana X Goldiana, D. Goldiana 
X intermedia , D. Goldiana X marginalis. 
D. cristata X spinulosa (Milde) C. Chr., recognized as occurring 
in New York, is not considered to be the equivalent of Dryopteris 
Boottii (Tuckerm.) Underw. which is, instead, referred to the new 
hybrid D. cristata X intermedia Dowell. D. Clintoniana X Goldiana 
Dowell is said to be the equivalent of D. Goldiana celsa Palmer, 1899. 
The principal points on which the writer bases his opinion as 
to the hybridity of the ferns in question are summed up as follows: 
“Each fern has characteristics common to two species and can not 
be referred to any one previously described species alone, except 
in the case of Boott’s fern, which has been described as a species: 
they have a tendency to be sterile, the sporangia being largely 
abortive; they occur only occasionally, and rarely in large numbers 
in any one locality; they grow in places favorable for the mingling 
of the gametes; they are found usually associated with the supposed 
parent species; hybrids among ferns have been experimentally pro- 
duced, and are known to exist.” Maxon. 
Rosenstock, E., Beiträge zur Pteridophytenflora Südbrasi 
liens. II. (Hedwigia. XLVI. p. 57—167. 1907.) 
In diesen Beiträgen findet sich eine grosse Zahl von für das 
Gebiet neuen sowie von überhaupt neuen Formen. Auch enthält 
dieser Teil einige Verbesserungen von im ersten Teil behandelten 
