3m; 



MR. J. • BAKER ON THE GEOGRAPHICAL DISTRIBUTION OF FERNS. 



* 



absence of individuality. There are only 13 species in all, not one of which is peculiar 

 „/ plm 'in, -,i H< it%8 and Notochlana lamiginosa are not tropical African, but they art 



' narian and Meditcrr 



and Nephrodium odoratum is not known nearer than 



Ma 

 V 



uinca 



Pot the west side of the continent, from Senegambia southward, through 

 Angola, the botany of which the recent explorations of Barter, Mann, and 



1 1 have done so much to make known to us. we 



enumerate 197 ferns 



47 of vt luCli are peculiar. Of these, 116 



common to both sides of the continent, 6 



1 inir rest rioted to Angola, and most of the other 41 to Guinea and Senegambia. A small 

 number (13) of West- African species are very interesting geographically, as being essen- 

 tially tropical, and common to tropical America and Africa, but absent from Asia. 



This 



the i ase with 



Hymenophyllum ciliatum. 

 Pteris Chilensis. 

 Trichomanes crispum. 

 Asplenium serra. 



dimidiatum. 

 cicutarium. 



Nephrodium subquinquefidum 

 Polypodium cultratum. 



N ephrodium hirtum 



rigescens. 



glaucophylluxii. 



Acrostichum hybridum 



villosum. 



Si nelena comes next of known floras to Tristan d' Acunha in the proportion which 

 Fere bear to Phaneroganiia, which is nearly as two to three ; and it is very remarkable 

 from the fact that half of them are peculiar to it. 



The St, Helenan list is as follows 



*Dicksonia arborescens. 



*Hymenophyllum eapillaceum 

 Cheilanthcs multifida. 

 Pteris flabeliata. 



* 



- paleacea. 



*Nephr odium cognatum. 

 ^Polypodium molle. 



marsrinellum. 



*Asplenium compressum. 



* 



- erectum. 



platybasis. 

 fur cat urn. 



lanceolatum. 



punctatum. 

 lanceolatum 



Monogramme, sp. 



* 



* 



nigro-paleaceum 

 Nephrodium patens. 



Napoleonis. 



graminoides. 



*Gymnogramma Haughtoni 

 "^Acrostichum dimorphum. 





bifurcatum. 



- subdiaphanum. 



- conforme. 



Ophioglossum vulgatum. 



The peculiar species are those marked with an asterisk 



the result as follow 



Analyzing the list, we find 



Species peculiar to the island 

 Common to Africa and America 

 African, not American 

 American, not African 

 Canarian, neither African nor Amer 



Total . 



13 



7 



2 

 2 

 1 



25 



