PART XI.] 
Blanford: Coasts of Persian Gulf. 
43 
I found a small outcrop of the Hormuz rocks on the island of Tumb. The only place 
on the main land of Persia at which I recognised the existence of this formation was at 
Ras Bostanah, north of Linga. I did not land, but the Commander of the Amberwitch, 
Captain Bishop, took the steamer as close to the shore as he could with safety, in order to 
enable me to see the rocks, and their appearance and surface were characteristic of the salt 
series. 
I can form no conception of the age of these salt beds: they are much disturbed, but 
beyond the fact of their being much older than the Makran group, there is nothing to 
indicate their geological relations. They appear to be unfossilifcrous. 
Makrtin group of beds .—Cape Monze on the western frontier of Sindh consists entirely 
of nummulitic rocks, chiefly limestone. Farther to the westward, the beds near the coast 
have an appearance entirely different from that presented by the nummulitics, the distinction 
being so great that it may be recognised at a distance of many miles. The prevailing rock 
along the Makran Coast is a pale grey clay, more or less indurated, occasionally intersected 
by veins of gypsum, usually sandy, and often calcareous, occurring in beds of great thick¬ 
ness. With this clay are interstratiiied bands of shelly limestone, calcareous grit, and 
sandstone, but these usually form but a small portion of the mass, although their greater 
hardness makes them conspicuous at the surface. In all sea cliffs and inland scarps the 
clay is well exposed; thus the magnificent cliff, nearly 2,000 feet high, at Ras Malan, is 
almost entirely composed of it. From its softness, it disintegrates rapidly, and the usual 
features of the scenery are peculiar and characteristic. Where the rocks of the Makran 
group are horizontal or slightly inclined, the hills near the coast, as at Ras Malan, Hormara 
and Grwadar, are more or less flat-topped, the upper surface composed of one of the hard 
calcareous beds, which are usually dark coloured or become so where exposed, forming a 
stony plain, often broken up by ravines. Hero and there, especially if the harder beds are 
few in number, isolated blocks of fantastic form stand up above the general level of the 
hills, precisely as in the horizontal traps of the western ghats, although the pale, almost 
white colour of the Makran clays gives them a very different aspect from that of the black 
basalts. The scar'ps around the hills are white or grey clay cliffs, often much concealed by 
the dark coloured debris of the calcareous bands. 
Where, on the other hand, as is sometimes the case,— e. </., near Jashk and some 
miles east of Hinglaj,—the rocks of the Makran group dip at considerable angles, the hills 
formed of them assume a very serrated appearance in consequence of the rapid washing 
away of the clays and the prominence given to the harder bands. Although this appear¬ 
ance is peculiar, it is less characteristic than that of the flat or nearly flat-topped hills 
surrounded by pale coloured cliffs. 
Locally, a peculiar appearance is produced by vertical veins of gypsum standing ujr 
in the clays, but this does not appear to be common. 
The “mud volcanoes” of the Makran Coast have long been known: they are numerous 
and those seeu by me at Chaudrakup appear to consist of the characteristic clay of the 
Makran group, which being mixed with salt water, is ejected by means of gas, and dries 
into cones. 
Fossils of Makran group .—The Makran beds are evidently of marine origin. They 
are usually highly fossiliferous, the most abundant fossils being species of Ostrea, Pecten, 
and JBalanm. Bivalve MoUusca, especially forms of Area (several species), Card him, Larina, 
and species of the family Veneridie, Sfc., abound, but very often only occur as casts ; Gastero¬ 
poda, though far from scarce, are less common, forms of Cerithium, Turritella, and Nation 
