1923] | Evans,—Notes on New England Hepaticae,—XVIT 79 
triangularis in his Plant. Crypt. Helvetiae. Since it is now admitted! 
that Schleicher’s J. triangularis is a nomen nudum, Lindberg’s 
combination B. triangularis, of 1875, represents the first adequate 
publication of the specific name triangularis for the plant in question 
and should not be allowed to replace the name tricrenata, which 
clearly dates from 1814. 
1900 Pearson? added to the nomenclatorial difficulties involved 
by recognizing both B. tricrenata and B. triangularis as valid species. 
He listed, as synonyms of the latter, Jungermannia triangularis 
Schleich. and J. deflexa Mart. According to Nees von Esenbeck, 
however, as already pointed out, both of these species are synonyms 
of his Herpetium  deflexum  tricrenatum, under which he naturally 
cites, as another synonym, J. tricrenata Wahlenb. It would appear 
therefore that J. triangularis and J. deflexa should both be cited as 
synonyms of Bazzania trierenata, when this is accepted as a valid 
species, and there is nothing in Lindberg's writings to indicate that 
he ever interpreted his B. triangularis in a different and more restricted 
sense. Pearson's B. triangularis of 1900 thus becomes a homonym 
of Lindberg's B. triangularis of 1875, in case each represents a dis- 
tinct species. 
The validity of Pearson's species, however, is not above question, 
and it is not at all certain that it represents a definite and clearly 
defined series of forms. According to his observations it differs from 
B. tricrenata in the following respects: the plants are smaller; the stems 
are more slender and usually, but not invariably, dichotomously 
“innovantly” branched; the leaves, which soon fall away, are pro- 
portionately shorter (except in the var. flaccida); the leaf cells are 
"rounder," with large and distinct trigones; and the underleaves 
are patulous and usually subentire. In the var. flaccida the leaves are 
described as narrower and often entire and apiculate. Except for 
the fact that the leaves are said to be caducous, instead of persistent, 
these differences might well come within the range of variability of 
such a species as B. tricrenata, and Pearson himself questions whether 
his B. triangularis may not be either the male plant or a mere variety 
of B. tricrenata. 
As a matter of fact the specunens cited under B. triangularis do 
not all show the caducous habit. In the material from Tyn-y-groes 
1 See Evans, Ruopora 10: 190, 1908. 
? Hep. British Isles 130, 132. pl. 48, 49. 1900. 
