Observations in the Sutlej Valley.'* 209 



limited region of those mountains, the Sutlej Valley, and is 

 therefore more local in its character. The species were col- 

 lected or observed during the summer months, from May to 

 October; while the authority for the winter residence of many 

 of them rests chiefly on the evidence of the specimens obtained 

 by shikarees employed to collect during the winter. 



One hundred and thirty-nine genera, belonging to the Inses" 

 sores, are enumerated as being represented in the Sutlej Valley. 

 Of the remaining eighty-nine genera, after deducting fifty which 

 are common to the temperate regions of the Old World and to 

 the plains of Continental India (such as Hirundo, Coracias, Me- 

 rops, Picus, Corvus, Sitta, Lanius, and so forth), forty-one of the 

 genera (like Palaornis, Pyctorhis, Tchitrea, Meyalama, Arach- 

 nechthra, Copsychus, Thamnohia, Dendrocitta, Zosterops, and 

 others) are strictly characteristic of the plains of India with their 

 lower elevations. Seventeen genera are common to the mountains 

 and elevated tablelands of the Himalayas, to Europe, to Central, 

 and probably Northern, Asia — Certhia, Cinclus, and Tichodroma, 

 for instance; seven are Himalayan genera, including, in all 

 likelihood, Central-Asiatic species, Hemichelidon, Propasser, and 

 a few more ; and twenty- four are genera peculiar, within the 

 Indian region, to the slopes, valleys, and jungles of the Hima- 

 laya. In the Central and Eastern Himalayan regions special 

 genera, containing numerous species, abound ; while in the 

 north-western Himalayas these characteristic genera and specific 

 forms rapidly diminish, and probably cease altogether before 

 the eastern bank of the Indus is reached. 



In his instructive preliminary sketch of the physical construc- 

 tion of the Sutlej Valley, Dr. Stoliczka supplies us with a ready 

 explanation of this apparently anomalous commingling of the 

 avi-fauna of such different zoological provinces. The Sutlej, 

 without making a long eastern or western circuit, like the Bra- 

 mapootra and the Indus, b'reaks, in an almost direct line to- 

 wards the plains, through the intervening ranges of gigantic 

 mountains, cutting its way, or bursting a passage, through the 

 solid rock, and jumping, in a course of 180, or in a straight line 

 of 110 miles, from an altitude of 13,000 to that of 1000 feet. 

 Its valley and those of its affluents thus provide an easy means of 



N. S. VOL. V. P 



