BRITISH JUNGERMANNIiE. 
(J. undulata.) 
however, which are evidently what he took for the seeds, very exactly correspond with those 
of our plant. After speaking of the leaves, he says, “ L’extremit.e de ces feuilles forme des 
especes de rosettes, dans le milieu des quelles se voyent. de petits grains jaunatres et transparents, 
qui selon toutes les apparences sont les semences de cette plante.” Dillenius has so well described 
the structure of the leaves of this species, that I shall here quote his words; “Aquae immersa 
obsolete ex fusco viridia folia sunt pcllucida, superiora versus majora, inferiora versus minora, 
subrotunda, supra convexa, infra concava, e duabus laminis ad basin unitis et complicatis 
composita, lamina minori superiori, seu ipsi pinnae imposita. Ea porro differentia observatur, 
quod extrema folia e laciniis penb aequalibus constent. Quoniam folia satis lata sunt, haec 
foliorum structura facilb percipitur, neque vero absimile, sequent ium specierum (J. nernoroste 
resupinatae et albicantisj, folia similiter formata esse, licet ob exiguitatem non tam facile distin- 
guantur. Pinnae per lentem non crenatae apparent.” 
The erect mode of growth, much larger size of the plant, and the smallness of the lobes com- 
pared with the leaves, are marks by which J. undulata may always be known from J. resupinata ; 
while the entire margins of the leaves and mouth of the calyx, as well as the. more delicate 
structure and undulated appearance of the former (which is particularly the case when the plant 
is dry), will equally distinguish it from J. nemorosa. The gemmae also differ both in color and 
situation. 
Pollich remarks, that the barren surculi of this plant produce at their apices “globulos 
nigricantes, pusillos, sex aut septem, etiam plures, sessiles,” which accord rather with the gemmae 
of J. nemorosa than with those that I have seen of J. undulata. 
FIG. 
1 . 
2 . 
3 . 
4 . 
5 . 
6 . 
7 - 
8 . 
9 . 
10 . 
11 . 
12 . 
13 . 
14 . 
REFERENCES TO THE PLATE. 
J. undulata, male plants, natural size. 
Female plants, natural size. 
Female plant, magnified 
Extremity of a male plant 
Portion of a stem with its leaves 
Extremity of a female plant 
Seeds and spiral filaments 
Perigonial leaf 
Perigonial leaf, with the lobule expanded for the purpose of exhibiting 
situation of the anthers 
Anthers 
Gemmaceous plants of J ■ undulata, natural size. 
Gemmaceous plant magnified 
Mass of gemma, removed from the plant 
Gemmae 
6 
6 
4 
5 
1 
3 
the 
..} 3 
1 
6 
4 
2 and 1 
