1922.] the Birds of Sind. 529 



Tlie mountains of the Khirthar run up to 4-5000 i't., the 

 highest peak being Uharj-aro, about GOOO ft. They are of 

 Tertiary formation, mostly nummulitic limestone^ butat Jjaki, 

 Cretaceous rocks are exposed ; however, some of the lower 

 slopes and various valleys, such as the Habb and B:trun, are 

 sandstone. The only formation different from the main hills 

 are the low hills in Naggar Parkar in the extreme south-east, 

 which are granitic rocks of the Aravalli Range belonging to 

 the Archaean system. 



But for the numerous canals supplied by the Indus, the 

 whole would be the dreary desert which the rest of Sind 

 outside the canal area is ; the canal influence is felt for a 

 breadth of country running more or less parallel with the 

 Indus from Kashmor to the mouth, covering a width of 

 about 50 miles. These canals, most of which have been 

 made since 1851)^ must have profoundly influenced the 

 original avifauna of the province. Thus the East Narra 

 Canal (1851*) with its branches Milhrao (187*.)) and Jamrao 

 (1899) brings into cultivation about half a million acres of 

 what would otherwise be desei't ; its course is roughly that 

 of the ''lost river of Sind^^ — the Hakro. As two-thirds of 

 the Narra water now flows down the Jamrao Canal, the con- 

 ditions of the country and status of some birds in its loAver 

 reach may well be altered from what it was in Doig's day. 



In extraordinary contrast to the desert portion, ISind con- 

 tains a vast number of fresh-water lakes or j heels known as 

 "dhands." After heavy monsoons, huge areas are inundated ; 

 while many pools exist for a few weeks onl}'; many "dhands, '^ 

 gradually shrinking in size, exist almost till the next hot 

 weather; others, again, are formed l)y canal overflows, and 

 some of these are practically perennial lakes, many of them 

 surrounded by tamarisk, reeds, rushes,etc., making a veritable 

 paradise for aquatic birds, notabl}^ the great JManchar Lake, 

 the largest fresh-water lake in India. 



The climate is dry and the temperature averages hi<>h. 

 In the hot weather, April-October, most of Sind is well-nioh 

 unbearably hot ; at Shikarpore, for instance, for weeks the 

 temperature at night never falls below 100° I\, and the shade 



SER. XI. — VOL. IV. 2 M 



