EVANS—THE NORTH AMERICAN SPECIES OF ASTERELLA. 283 
californica and female material of Clevea hyalina californica Howe. He 
recommends that in order to avoid confusion the specific name*limbata be 
given up altogether, in spite of the fact that Sauteria limbata antedates Fim- 
briaria californica by several years. 
The slime cells of A. californica have apparently been overlooked by previous 
observers. They occur without definite order in both green and compact tis- 
sues and are distinguished by their large size and colorless, highly refractive 
contents. They are sometimes more numerous in the green tissue, sometimes in 
the compact tissue, and sometimes equally numerous in both. In exceptional 
cases they may be very abundant, as many as 50 having been seen in a single 
section, but they are usually more scantily developed and may be absent alto- 
gether. Since slime cells have not been detected in other species of Asterella, 
their presence will sometimes help in the determination of sterile material. 
The ventral scales of A. californica bear a certain resemblance to those of 
Reboulia hemisphaerica and have perhaps been the cause of confusion. In both 
plants the scales are characterized by slender and long-pointed appendages, 
their number varying from 1 to 3 or 4. In the Asterella, however, these ap- 
pendages are subulate, tapering from a broad base, and are separated from 
one another by sharp sinuses; while in the Reboulia the appendages are linear 
from a very narrow base and are marked off much more sharply from the basal 
portion of the scale, being separated by a considerable length of margin. In 
the frequent possession of 8 or even 4 appendages the scales of A. californica 
are distinguished from those of most other species of Asterella. 
Other unusual features of A. californica are the dioicous inflorescence, the 
‘deeply lobed female receptacle, and the bipartite involucre. The margins of 
the last are not always entire, as stated by Stephani. Those studied by the 
‘writer show scattered rounded teeth, some of which represent projecting cells, 
while others are 2 cells in length. The yellow spores, with their distinct mar- 
ginal wings, fine surface reticulum, and sparsely developed ridges on the 
faces, are also very distinctive of the species. A. californica sometimes grows 
in company with A. palmeri and the two species resemble each other some- 
what in a sterile condition, both having a more. or less pigmented margin, 
which becomes incurved when dry, and both developing large purple ventral 
scales. A. palmeri, however, is a somewhat smaller plant, the dorsal air cham- 
bers are not subdivided, and the scales rarely have more than one appendage. 
Of course, if the conical and scarcely lobed female receptacles are present, the 
species can at once be distinguished. 
¥. Asterella lindenbergiana (Corda) Lindb. 
Fimbriaria lindenbergiana Corda; Nees, Naturg. Eur, Leberm. 4: 283. 1838. 
Fimbriaria maior Hampe; Nees, loc. cit., as synonym. 
Marchantia alpina Schleich.; Nees, loc. cit., as synonym. 
Fimbriaria bonjeanii DeNot. Mem. Accad. Sci. Torino II. 1: 335. pl. 1, f. €. 1839. 
Asterella bonjeanii Trevis. Rend. Ist. Lombardo II, 7: 777. 1874. 
Hypenantron bonjeanii Trevis. Mem. Ist. Lombardo III. 4: 440, 1877. 
Asterella lindenbergiana Lindb. Musc. Scand. 1. 1879. 
Hypenantron lindenbergianum Kuntze, Rev. Gen. PL 1: 89. 1891. 
Fimbriaria commutata Stephani, Bull. Herb. Boiss. 7: 209. 1899. 
Thallus sometimes green above but often more or less pigmented with red 
or purple on both surfaces, mostly 1 to 3 cm. long and 4 to 6 mm. wide, plane or 
with the undulate-crispate margins somewhat incurved when dry, usually with 
a shallow and narrow median furrow, branching by forking, the keel narrow 
and often sharp; epidermis composed of thin-walled cells without trigones, aver- 
