THE FERRAR GLACIER 95 



Similar moraines occur at Dry Valley and at the stranded moraines. 



Dry Valley. The area was originally occupied by the north-eastern fork of the 

 Ferrar Glacier, from which the ice has now retreated, and at present it is covered 

 by a thick deposit of morainic debris. One of the most interesting features of Dry 

 Valley is the occurrence there of a raised beach. This will be described in detail in 

 the part of this work relating to raised beaches. 



It may be stated here that enormous numbers of the delicate shell Pecten 

 Colhecki with both valves attached to each other were found in position and quite 

 unbroken up to 50 feet above sea-level. 



The general appearance of this valley is shown in Plate XX. Fig. 2. 



There were large mud-flats bordering the ice-foot in this valley, and these 

 reached their greatest extent where they were augmented by the deltaic material of 

 the many streams draining the valley, and on them, a few feet above the present 

 sea-level, numerous specimens of amphipods and sea-spiders and one small fish were 

 secured, all in a much desiccated condition. It is not necessary to postulate a 

 recent rise in the level of the land to account for these specimens, since in the 

 short period when the sea is released from the control of its icy winter covering, 

 a strong wind blowing directly into the bay would inevitably cause a rise in the 

 level of the water sufficient to assure the submergence of those portions of the mud- 

 flats immediately adjacent to the ice-foot. Upon the recession of the sea numerous 

 animals would be left stranded in any slight depression in the recently covered 

 flats, and evaporation and ablation would remove the sea water during the late 

 summer and autumn, leaving the desiccated remains of the animals, and giving rise 

 to an efilorescence of salt on the surface of the mud. Indeed the sequence of events 

 might very well have been caused by the very blizzard which raged from February 

 20th to the 22nd, 1908, when the Nimyocl was driven north. 



The remaining features of the Dry Valley moraines are very much a repetition 

 of those of the Stranded Moraines, but on a much larger scale. The interesting 

 discovery was made that at a height of between 500 and 600 feet there was an 

 abundance of erratics foreign to the valley, namely, kenyte and basalt and tuff's 

 appertaining to these two types.* These rocks had in no wise diminished in relative 

 proportion inland, as compared with the rocks obviously derived from the sides 

 of the valley, or from the higher reaches of the glacier. 



Only two of the many thaw-water channels which furrow the district are still 

 filled with running streams. The rest at the most are occupied only by a string of 

 stagnant pools, while numerous depressions of smaller extent, with a heavy efflor- 

 escence of salt coating the gravel, mark the site of former pools. 



The most northerly and most flourishing stream in the Dry Valley has cut a 

 channel of 50 feet deep through the stratified gravel, the sides of which slope 



* The Western Party of the Scott Expedition 1910-13 have since examined this district in detail, 

 and Debenham found kenyte and basalt in situ in the upper reaches of the glacier. 



