POLYPODIUM CALIFORNICUM. CALIFORNIAN 1'()LVI'()I)^■. 35 



condition on our plate. The reason is that about the time when 

 our species was first discovered the condition of the veins was 

 supposed to be more ujichangeable than it is known to be now. 

 In some places a form was found like it that did not have die 

 netted veins, and it was thought therefore to be another species, 

 and named by Hooker and Arnott Polypoditim mtermediwn ; but 

 as more specimens were discovered some of the former w^ould 

 occasionally be found with free veins and some of the latter 

 with netted veins, and therefore in this case at least the character 

 is worth nothing as a distinction. Consequently Hooker, in his 

 "Species Filicum" published in 1864, united the two, and they are 

 now both known by the oldest name P, Calif orniatiu . Our plant 

 in its earlier history would have been probably known as 

 P. intermediiuu. 



Whether a form is to be considered as a distinct species or 

 as a mere variety depends very much on experience as to the 

 fixity of characters, rather than on any specific points that can be 

 readily explained ; and we can see in this case that only for the 

 fact that a few netted veins had been found in one case, and a 

 few free veins in another case, both forms would in all probability 

 be regarded as distinct species to this day ; and it is such facts 

 as these which make observations on the range of variation in 

 species of so much value to practical botanists. In ferns espe- 

 cially very much has to be learned on this point. For want of 

 this knowledge synonyms are very numerous. In the case of 

 our present species. Professor Kunze, in a paper translated in 

 " Silliman's Journal," new series, Vol. 6th, remarks that Hooker 

 and Greville, standard authors on ferns, had united very differ- 

 ent species with it. Another writer in the 6th Volume of the 

 " Bulletin of the Torrey Botanical Club " suggests a doubt 

 whether another species of the Pacific Coast, Polypodhim falca- 

 tuni, may not be referred to P. Californinmi. Botanists may not 

 be wholly prepared for this view yet, although we incline to it; 

 but it shows how uncertain much fern knowledge yet remains. 



A very pretty feature in our Californian Polypody is its trans- 



