DESCRIPTION OF SPECIES. 315) 
BRYOPHYTA. 
Order HEPATIC&. 
HausMannia riGIpaA Newb. n. sp. 
Pl eS 2. (oO: 
Frond large, bipinnate or tripinnate, flat; central line of pinne and 
pinnules traversed by a strong continuous midrib, from which are given off 
many fine, flexuous, branching veins. Margins entire, pinne and pinnules 
mostly opposite, pinnules linear, subacute. 
This interesting plant is not uncommon at South Amboy, and a single 
fragment of it has been found at Woodbridge. It is evident, however, that 
it belongs to the upper beds of the Amboy Clays, and was an inhabitant of 
the region around New York Harbor only in the last half of the Amboy 
epoch of the Middle Cretaceous period. 
It closely resembles Hausmannia dichotoma of Dunker (Monographie 
der Norddeutschen Wealdenbildung, p. 12, Pl. V, fig. 1; Pl. VI, fig. 12), 
but is far more exact and regular in the divisions of the frond, and they 
are not dichotomous. In regard to the botanical affinities of this plant, our 
specimens do not solve the problem. In my judgment, it is a fern or 
hepatic, though no living fern comes very near to it. 
From a resemblance which appeals rather to instinct than reason, I 
have been led to think it possible it was a higher kind of hepatic, a Mar- 
chantia, for example, lifted from its creeping condition into an independent 
and erect plant, trained and disciplined into symmetry by the occult influ- 
ence which has given such grace and exactness to the foliage of ferns, 
lycopods, and some conifers. 
Probably future collections will solve this problem, but until the 
fructification shall be found this will remain one of the most puzzling 
forms of extinct vegetation. 
Among fossil plants Rachiopteris (formerly Schizopteris) seems to 
me to be most like Hausmannia, but no species of that genus shows any- 
thing like the regularity and symmetry of structure which are conspicuous 
characters in the plant before us. 
Localities: Woodbridge, South Amboy. 
