282 Capt. Lynes on the Ornithology [Ibis, 



from the other halP all the species that preserve a coinmou 

 form over a very wide area, or practically the whole of their 

 known range, there remain hut three or four subspecific 

 forms, Green finah, Linnet, Imperial Eagle, and perhaps 

 Wood lark, common to the two territories. 



Or, taking anotlier view : out of the 4:2 species common 

 to, but represented by different races in Maiiretania and 

 South Spain, 24 (only) are of race peculiar to the latter, the 

 remaining 18 are all of races that extend far and/or wide on 

 the European Continent, the most remarkable perhaps being 

 the Magpie, (Jhalfinch, Nuthatch^ Missel-Thrush, and lied- 

 legged Partridge. 



Viewed in either of the foregoing aspects, one cannot help 

 observing the singular influence of the eight mile wide 

 Straits of Gibraltar as a suhspecific boundary between 

 Euro[)e and Marocco. 



It now Vemains to examine distribution within the bounds 

 of Mauretania itself; but here, even in the Bird " Class'' we 

 are confronted by the following serious obstacles : — 



(a) The Riff, except at its extreme northern end near 

 Tetuan is quite unknown. 



(//) The western Great- Atlas and north-east branch of the 

 Middle-Atlas, containing the dominant massif of the 

 range, as well as the Marocco-Algerian confines, are 

 quite unknown. 



(r) The Desert-slopes of the Gieat-Atlas are practically 

 unknown. 



((/) The mountains of Western Algeria and the Saharan- 

 Atlas Range have so far only been *' skimmed,'" and 

 the same maybe said of all the remainder of Marocco 

 except the Atlantic seaboard, the western extremity 

 of the Great-Atlas, and the neighbourhood of 

 Tangier. 



But even these serious limitations scarcely obscure two 

 outstanding distributional facts in Mauretania. 



