IN CALIFORNIA 169 



ture combined with steady warmth. California as 

 a whole, is dry rather than moist, and the tempera- 

 ture runs a scale of anywhere from twenty to forty 

 degrees every day in the year, between dawn and 

 midnight. It is not surprising, then, that of all 

 the ferns which thrive in the relatively wet and 

 equable conditions of the Eastern summer, there 

 are but a scant half-dozen that find Calif ornia r s 

 chilly nights and low midday humidity at all toler- 

 able. Moreover these are by no means frequent. 

 They are the common polypody (Polypodium vul- 

 gar -e), which may be found along the northern coast, 

 often rooted in the damp crevices of the bark of tree 

 trunks; the five-fingered maidenhair (Adiantum pe- 

 datum) which occurs here and there in the Sierra 

 Nevada and in the Coast Eanges of Northern Cali- 

 fornia; the true maidenhair of the Old World and 

 the Atlantic South (Adiantum Capillus-Veneris), 

 which occasionally finds wet, shady rocks in South- 

 ern California to its taste ; the lady-fern (Asplenium 

 Filix-foemina), in mountain bogs; and two woodsias 

 of the High Sierra, which occur also as far east as 

 the Mississippi basin. A number of common favor- 

 ites of the East, such as the several osmundas, the 

 sensitive fern, the walking leaf and the sweet- 

 scented dicksonia of mountain pastures, are en- 

 tirely wanting on the Pacific coast. 



