1862.] Notes of a trip from Simla to tlie Spiti Valley. 519 



the} 7 are viviporous, one female containing three fceti, though two 

 seemed the commoner number. This departure from the plan of 

 oviparous reproduction usual among lacertines seems intended to 

 meet the exigencies of a severe climate, for in a region where snow 

 sometimes falls at midsummer, eggs exposed in the usual manner 

 would run considerable risk of having their vitality destroyed by an 

 untoward frost. Those naturalists who adopt Darwin's theory of 

 "natural selection," and the progressive mutation of species, will 

 find it an interesting problem to explain (rejecting the old fashioned 

 view of creative adaptation I have assumed above) how the oviparous 

 progenitors in mythical times of these lizards came to adopt or ac- 

 quire a viviporous organization, one problem of the many which the 

 new dev elopement theory, I should say " Natural selection" raises 

 at every step. Near the camp the shores of the lake were perforated 

 by the holes of a short-tailed rat or lemming, . JPhaiomys leucurus, 

 Blyth. Their holes frequently were ranged in a long line against a 

 bank and usually extended so far that all attempts to capture an 

 animal by digging or flooding the holes with water proved fruitless. 

 Alter infinite trouble, however, I managed to dig out an adult female, 

 which on examination I found to contain six young ones the size of 

 horse beans, three in each horn of the uterus. The total length of 

 this specimen was 6.15 inches, of which the head was 1.30, and the 

 tail 1.25. Colour yellowish mouse brown, merging into pale gray 

 beneath. This colour, however, only extended to the tips of the hair, 

 the body of each hair being dark slaty -blue only visible when the 

 fur was thrown back ; fur loose, length, three-eighths of an inch ; 

 whiskers, seven-eighths ; ears rounded, medium size, rather oppressed. 

 I subsequently got several more, mostly half-grown, by watching 

 near their holes with a gun. 



18th. — Camp a little below halting-place of the 15th. 



19th, Phalang-palra. — A mere halting-place among loose rocks 

 which afford shelter from the wind. A few miles from last night's 

 camp recross the Para river, which here was in several channels, in 

 two of which the water nearly reached to a man's hips. 



20th, latung. — (Tratung Kongma of Cunningham). A mere halt- 

 ing-place close to the highest limit of furze on the west bank of the 

 Para river, a little above where I halted on the 13th. Sleet fell clur- 



