Miscellaneous. 75 



On the OeograpJiieal Distribution of the Ferns of Mexico. 



By EUGEXE FOUKNIER. 



The author has carefully examined the specimens of Ferns from 

 Mexico in almost every collection existing in Europe, and arrives 

 at the following results : — The number of species, which was given 

 as 6 by Kimth, 182 by Martens and Galeotti, 312 by Liebmann 

 (omitting synonymic forms), and 487 by Fee (of which 70 are to be 

 suppressed), amounts, according to the author, to 605, besides a few 

 others of which he has not seen specimens. Of this number, 47 are 

 now indicated as Mexican for the first time ; and 217 supposed species 

 are suppressed as identical with others previously described. 



The species of ferus are generally the same on both slopes of the 

 Mexican Andes. Of the species enumerated by Smith as collected 

 in the Sierra Madi^e on the Pacific slope, only three have not yet 

 been discovered on the Atlantic side. 



The author identifies a far greater number than his predecessors of 

 Mexican species with species growing in other parts of America, 

 especially between the tropics. Of his 605 species, only 178 are 

 peculiar to Mexico ; and these belong to groups largely represented 

 in that country and wanting elsewhere in tropical America. Of the 

 427 species common to Mexico and other regions of America, 230 

 occur in the Andes of South America (Kew Granada, Ecuador, Peru, 

 Bolivia), 139 in the Antilles (especially Cuba and Guadeloupe), 59 

 in Guiana or Caraccas, and 117 in Brazil, the greater part extending 

 as far as Rio de Janeiro. The ferns of the high mountains of 

 Mexico easily find a suitable climate in the Andes, even under the 

 equator ; 12 of them also pass beyond the intertropical region and 

 descend into the province of Corrientes or to Montevideo, and 17 

 extend into Chili. Many of the latter, especially the PeJlo'ce, pass 

 into the mountains of Texas, whence 1 1 have been brought bj Trccul. 



The species of the neighbourhood of Orizaba and Jalapa growing 

 at from 1000 to 1500 metres in the eastern Cordillera of Mexico, and 

 some of which live in Florida or Carolina, also occur in part in Guiana, 

 and most of them in Cuba and at Rio de Janeiro ; some species even 

 occur in Mexico and at Rio de Janeiro and are not at present known 

 from any intermediate place. 



The very few littoral species of ferns found in Mexico are gene- 

 rally difi'used over the whole tropical region of the globe. 



The most interesting group is one composed of only 12 species, 

 which, starting from the bottom of the Mexican Gulf, and passing 

 the Antilles, reaches the Azores and Canary Islands, then becomes 

 difirised over the Mediterranean region and is continued by a small 

 number of species in the mountains of Abyssinia and Persia and in 

 the Himalaya. Of these, in passing northwards, Pteris lonr/ifolia 

 stops in the island of Eschea, P. cretacea in Corsica, Woodwardia 

 radicans in the mountains of Asturias, Adiantum ccqidhis at Poitiers 

 and at Bormio in the Tyrol near a hot spring, and Gi/mnor/ramnm 

 leptophiilJa at Brest, whilst Cystopteris frar/ilis, a polymor})hic but 

 indivisible species, spreads all over Europe and reaches the summits 

 of the Alps. The authentically established existence of this group 

 of plants agrees, in the author's opinion, with the hj-pothesis of 



