GEOGRAPHICAL DISTRIBUTION 337 



the shores of the Atlantic, for throughout that immense tract species 

 of Passeres are found that wear the Desert uniform and scarcely differ 

 from one end to the other. 



Having already indicated the component parts of the Subregion, 

 it is time to say somewhat of its ornithic characters. Like the 

 Nearctic, it seems to produce but a single peculiar Family of Birds 

 — the Panuridse, the type of which is the beautiful species known 

 to most Englishmen as the Bearded Titmouse, Panurus hiarmicus ^ ; 

 but this fact need excite no surprise when we remember that along 

 almost the whole of its southern frontier-, extending from long. 120° 

 E. to 10° W., it is conterminous with the Indian or the Ethiopian 

 Region, whereas the Nearctic Subregion presents not more than 20° 

 of latitude to the Neotropical Eegion.^ Indeed, the wonder rather is 

 that the Palaearctic Subregion should have even a single peculiar 

 Family, for we ought to bear in mind that all the Families of the 

 Holarctic Region consist of stronger forms than those inhabiting 

 the Regions which abut upon it, so that the faculty of extending 

 their range is possessed in a greater degree by the former. The 

 whole number of Palsearctic Families may be taken to be 67, and of 

 the genera 323, about which there can be little doubt, or if any 

 exist, it is that the number is understated. Of these, as before 

 stated, 128 are common to the Nearctic Subregion. Species of 51 

 more seem to occur as true natives within the Ethiopian and Indian 

 Regions, and besides these, 18 appear to be common to the Ethiopian, 

 without being found in the Indian, and no fewer than 71 to the 

 Indian without occurring in the Ethiopian — a result that might be 

 expected from geographical considerations, since the latter Region 

 is cut oiFby a wide desert, constituting (as above stated) a barrier 

 as hard to pass as a sea, while the former Region, though in fact 

 separated by one of the highest mountain-ranges in the world, is 

 in almost its whole length conterminous. 



Taking the Provinces separately, we find that the Siberian has 

 but one genus peculiar to it — Eurynorhjnclius, the Spoon-billed 

 Sandpiper, a bird of wide wanderings, whose home was finally dis- 

 covered by the companions of Baron Nordenskjold on the mainland 

 opposite to Burney Island (long. 174° W.) during the memorable 

 voyage of the 'Vega.'^ The Mongolian seems to have the largest 

 number of peculiar genera of any Palaearctic Province, there being 

 no fewer than 13, which may be assigned as follows — Fringillidse, 



^ This bird is most unhappy in its names. It has nothing whatever to do 

 with the TiTMOtrsB-Family, Paridae, and its specific title, signifying of or belong- 

 ing to Biarmia, the district of Perm in Russia, is just as inapt. 



2 As the southern boundary of both Subregions lies in much the same latitude 

 (say roughly 30° N. ), the degrees of longitude are practically equal in either case. 



^ Palmen, Bidrag till Kdnnedomen om SihirisTca Ishafshustens Fogelfauna. 

 Vega-Expeditionens vetenskapliga lakttagelscr, v. pp. 326, 327. 



22 



