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the Jordan valley, a long strip of country, greatly depressed, which is strictly tropical in climate, 

 and which belongs to the Ethiopian Region. Here one finds several purely non-European forms, 

 such as Nectarinea osea, Amydrus tristrami, Ketupa ceylonensis, and Struthio camelus, which I 

 have consequently excluded from the present work. 



On the islands included in this subregion are several representative species not found else- 

 where, as for instance Regulus maderensis, Anthus bertheloti, Serinus canarius, Fringilla tintillon, 

 Fringilla teydea, Pyrrhula marina, Cypselus unicolor, Columba bollii, Columba laurivora, and 

 Columba trocas; and the Blackcap of the Azores is subject to melanism in those islands, which 

 does not appear to be the case elsewhere. Although so far distant from the continent of Europe, 

 the Azores being quite alone in mid Atlantic, the fauna of these islands is strictly Palsearctic, 

 and it would appear that they have been peopled chiefly by stragglers from the continent of 

 Europe, in proof of which Mr. Godman points out that the bird population is most abundant in 

 the islands of the Azorean group which are nearest to Europe and Africa. 



Mr. Wallace includes the Cape-Verd Islands in the Palsearctic Region, and remarks (Geogr. 

 Distrib. of Anim. i. p. 215) that, though there is a mingling of the two faunas (Palsearctic and 

 Ethiopian), " the preponderance seems to be undoubtedly with the Palsearctic rather than with 

 the Ethiopian. I owe to Mr. R. B. Sharpe, of the British Museum, a MS. list of the birds of 

 these islands, twenty-three species in all. Of these, eight are of wide distribution, and may 

 be neglected ; seven are undoubted Palsearctic species, viz. Milvus ictinus, Sylvia qtricapilla, 

 S. conspicillata, Corvus cor one, Passer salicarius, Certhilauda desertorum, Columba livia; three 

 are peculiar species, but of Palsearctic genera and affinities, viz. Calamoherpe brevipennis, 

 Ammomanes cinctura, and Passer jagoensis. Against this we have to set two West-African 

 species, Estrilda cinerea and Numida meleagris, both of which were probably introduced by 

 man, and three which are of Ethiopian genera and affinities, viz. Halcyon erythrorhyncha, 

 closely allied to H. semiccerulea of Arabia and North-east Africa, and therefore almost Palse- 

 arctic, Accipiter melanoleucus, and Pyrrhulauda nigriceps : [the last two] are Ethiopian forms ; 

 but the same species occur in the Canaries." According to this there is much to be said in 

 favour of extending the Mediterranean subregion to include the Cape-Verd Islands ; but, after 

 carefully considering the matter, I have deemed it inexpedient to do so. 



It is chiefly during the seasons of migration that the rarer stragglers are met with within 

 our limits, and, as a rule, more frequently in the autumn than in the spring. Migration is a 

 subject which has only been investigated with any degree of care during the last few years ; and 

 as yet, comparatively speaking, but little is known respecting it. We have arrived at the know- 

 ledge of the fact that our Swallows pass the winter in South Africa and do not hibernate, and 

 that the Cuckoo does not become a Sparrow-Hawk in the winter, as was firmly believed within 

 the last hundred years ; but we have yet much to learn. Mr. Gatke has, during his long 

 residence in the island of Heligoland, collected a fund of information on the subject, and has 

 probably done more than any one else to further our knowledge on this subject; and I may 



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