82 



of the great central valley of California, and the heavy ocean 

 fogs which prevail during the whole summer undoubtedly miti- 

 gate to a very considerable degree the complete lack of rain. 

 Nevertheless, during the dry season the liverworts remain abso- 

 lutely dormant and apparently quite dried up. 



The hepatic flora in the neighborhood of Stanford University is 

 a very interesting one. There are types of most of the more 

 important groups, and almost without exception the common 

 species develop their reproductive organs in great numbers — 

 indeed in most of our common species one almost never meets 

 with sterile individuals. Besides the liverworts proper, several 

 species of Antliocci'os occur, two of which are extremely abun- 

 dant. With the exception of the genus Spliacrocarpiis, which 

 seems to be annual, all of the species in this neighborhood that 

 have been examined remain alive during the summer, and resume 

 growth promptly with the advent of the autumn rains. 



Among the most abundant liverworts of this region are several 

 species of Riccia, some of which, like R. trichocarpa,"^ grow in 

 very exposed places, subject to the full force of the sun. Of the 

 higher Marchantiaceae,the commonest species are Fimbriaria Cali- 

 fornica {AstcrcUa Californica) and Targioiiia liypopJiylla. Less 

 common are Fimbriaria Bolandcri {Aster ell a Bolandcri) and 

 Cryptomitriiim tcncrnm. 



In the moist forests of the outer coast ranges, and sometimes 

 straying down the banks of the streams, occur the cosmopolitan 

 Marcliantia polyvwrpJia and Fcgatclla conica {Conoccplialnni co?i- 

 iciiiii). It is doubtful, however, whether either of these species can 

 survive such complete drying up as that which the characteristic 

 species of the valley regularly undergo. 



The number of leafy liverworts is relatively small. The com- 

 monest species are Porc/Ia Bolandcri and Frullattia Bolaiidcri, 

 botii of which are abundant. 



Two species of Spliacrocarpiis and one o{ Fossovibrotiia — F. 

 longiscta — represent the thallose Jungermanniaceae. 



The Anthocerotaccae comprise two common species of Aiitlio- 

 ccros, A. fusiformis atid A. Pcarsom.\ 13oth of these species, 



* This is R. hirla of the writer's " Mosses and Ferns." 

 t //. laeris of •' Mosses and Ferns." 



