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MR. W. BATESO^f ON SOME VARIATIONS OF CARDIUM EDULE 
visit are also without Aral shells. I made particular and independent inquiry from 
many of the Kirghiz who live in various parts of the Kara Kum, showing them 
Cockle shells {Aigulak), and asking if they knew any localities where they were found. 
They all said that they had seen them at Jaksi Klich, Jaman Klich, and Shumish 
Kul, which are in the depressed regions, but they had never seen them in any other 
locality. I made special inquiry with regard to Aids Kul, which is marked on the 
maps as a considerable depression lying to the east of the Kara Kum, and I was told 
by several persons, independently, that no such shells were found there. For these 
reasons, it seems that, though the Aral Sea has retired within recent times from such 
an area as would be covered by it if its level were about 15 feet liigher than it now is, 
yet it cannot be shown that it has continuously receded from an area much larger 
than this. If it ever exteiided over the Kara Kum northwards to Tschalkar, this 
must have been in the remote past, and its disappearance from the definite shell- 
covered area must have been a comparatively recent event, not continuous with its 
disapjiearance from the larger and vaguely defined region which it is supposed to have 
covered in later Tertiary times. 
Special Account of the Basins Jaksi Klich, Jaman Klich, and Shumish Kul. 
The region where the greatest exposure has taken place is situated to the north 
and east of the Sary Cheganak. Here the sandy coast slopes very gradually to the 
sea, and at the post-station Alta Kuduk, for example, the shell-covered region is 
about 3-4 miles wide. But at Ak Jalpas there is a dry channel running up from the 
bay, which divides into two branches, the one running east and north, and the other 
running south. The latter has a course of about six miles ; near Ak Jalpas it is 
about half a mile wide, and is covered with mud, which is impassable after rain. 
Further south the channel narrows, and in some of the deeper holes in it there is 
always a little very salt water. This channel runs in a depression between the hills 
Ak Jar and Bultuk, and then opens out into a great depression, lying east and west, 
for a distance of about 8 miles. This place is known to the natives as Shumish Kul. 
(It is marked on the Russian maps as “ Khan Sultan.” This name is not known on 
the spot, though the mountain at the east end of the lake is called Khan Turt.) 
The appearance of this lake is very striking. The north and west shores are formed 
by bare hills, with a few bushes and coarse grass at their base. Thence to the bottom 
of the lake is a tract of undulating sand, bearing scanty vegetation. Below the sand 
a stretch of baked mud is exposed, surrounding the pan of salt which fills the lowest 
part of the lake. The salt lies in large contorted sheets, overlaying each other like 
frozen waves of muddy ice. On the eastern and southern shores, which shelve away 
gradually to more distant hills, are great flats of salt mud covered with Salicornia, &c. 
The biological interest of this place lies in the fact that upon the steep western 
shore are marked very definite terraces, showing the position of the water at different 
