18 RICCIACEAE 
Exsicc. Hep. Вог.-А т. 143” (as А. ит да Lindenb.). 
ep. Ат. 138* (as A. arvensis Aust, var. hiria 
Aust.). 
. On rather dry and rocky soil. About San Francisco, “ Mis- 
sion Dolores," “ Turk St.," “near Ocean House" (Dr. Bolander), 
Mission Dolores (Howe); Berkeley (Howe); Ukiah (Howe); near 
Stanford University} (Prof. D. Н. Campbell, Palo Alto (S. E. 
Brown); Santa Ana Hills (Parish); Pasadena (McClatchie); San 
Diego (Mrs. Katharine Brandegee). 
The above is the Californian Riccia that has been referred 
variously by American authors to Riccia ciliata Hoffm., В. tumida 
Lindenb., А. intumescens Aust. MS., Underw. (К. citata Hoffm. vat 
intumescens Bisch.) and more recently to Riccia hirta Aust. (К. 
arvensis Aust., var. та Aust.). But Riccia arvensis иа“ known 
only from Mr. Austin’s specimens from the neighborhood of 
Closter, New Jersey, bears comparatively few, short, usually blunt- 
pointed and incurved papilla-like cilia .1-.3 mm. long (not 52722), 
the thallus is strongly incrassate-carinate ventrally, the margins 
are acute, the epidermis is very thick, of 2 or 3 layers of de- 
colorate or purple-tinged cells, the somewhat smaller, more dis- 
tinctly margined spores are fuscous-brown at maturity and always 
show their areolae quite clearly in glycerine instead of being 
densely black and opaque as in A. trichocarpa under the same 
treatment, the plants are mainly smaller and less frequently dichot- | 
omous, Ше thallus-segments. are usually comparatively broader, 
reddish-purple below and more evidently squamigerous. 
А much nearer ally of Acca trichocarpa is doubtless Ж. ciliata | 
Hoffm. of Europe. From Ше typical form of this, however, the 
Californian plant is clearly distinct in the shorter and much more 
abundant setae (these often reach 1 mm. in length in А. са), in 
the presence of trichomes over the sporogonia, in the rather larger | 
size of the thallus, more acute-angled dichotomy, and іп the com- | 
monly black margins and sides: From R. ciliata intumescens | 
* See footnote, Bull. Torr. Bot. Club, 25 : 186. 1898. 
T Professor Campbell’s specimens, which we took as the type of this species, were | 
ер. Am., by error, as having been collected in San Mateo Со., | 
да this locality was зи in co Асла with our original description. We are ше 
rmed, however, by P a а that the e came from Santa Clara Co., . 
distributed in the He 
near the San Mateo Co. 
a 
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