group that those ferns are found which are distinctively or ex- 

 clusive Californian, and which are the most interesting and char- 

 acteristic. 



In the following list I am able, from personal knowledge, 

 to speak with some accuracy of the distribution of the ferns 

 in the southern counties. For the rest I have been obliged to 

 rely on published statements, on the examination of collections, 

 and on the kind assistance which has been given me by several 

 valued correspondents. Printed authorities are few, and in many 

 ways unsatisfactory. Eaton's elaboration of the pterodophytes 

 in the Botany of the Geological Survey, although published 

 twenty-three years ago, is to-day far the best — I may say is the 

 only valuable presentation we have of these plants. The dis- 

 tribution of the species is given as accurately as the knowledge 

 then accessible permitted. Since that date, besides general 

 works, as those of Underwood. Gilbert and Maxon. two papers 

 on western ferns were published in 1882 — Lemmon's Ferns of the 

 Pacific Coast, and Jones' Ferns of the West. But the scope of 

 all these papers permits, for the most part, only general state- 

 ments, the whole State being regarded as a unit in the definition 

 of distribution. There are but two or three local lists in which 

 the ferns are enumerated. They are entirely ignored in the two 

 manuals recently issued for central California — Greene's Flora 

 of the Bay Region, and Jepson's Flora of Western Middle Cali- 

 fornia. 



The present list is, then, to a considerable degree, merely 

 tentative. But so far as it goes, it is thought to be correct. For 

 in no case is a limit stated unless upon what is believed to be 

 good authority. It is altogether probable, therefore, that in some 

 instances the actual limits of species are under stated. But this 

 appears preferable to risking an over statement, even on the most 

 probable conjecture. When a general statement is made, as 

 that a certain species occurs "throughout the State," it is always 

 to be understood that the desert region is excepted, unless it is 

 expressly included. 



In the preparation of the list I have been greatly aided by 

 valuable notes obligingly communicated by Mrs. N. L. Britton, 

 Miss Alice Eastwood. Mr. A. A. Eaton, Prof. A. W. Evans, Mr. 

 B. D. Gilbert, Mr. W. R. Maxon, and Dr. L. M. Underwood, 

 whose kindness I take this opportunity of acknowledging. 



