Notices of Memoirs—Ancient Volcanoes of Basutoland. 463 
Hill, indicating there also the existence of higher beds than previously 
known. Its composition was much like some forest marbles, entirely 
differing from that of beds above or below, though traces of a similar 
structure occurred less regularly, but never as a definite layer or seam, 
in other parts of the section. 
The horizon of Wilson’s type-specimen of Hodiadema granulata had 
never been definitely ascertained, nor indeed that of the majority of 
the Gasteropods, etc., described by him as coming from Tilton, but 
found in the débris used in the construction of the East Norton 
embankment. 
The Billesdon Coplow section solved this question, for there the 
same Echinoderm was found with a number of the same genera and 
species of Gasteropoda, Cephalopoda, etc. It had also been found by 
others, and there was an example from Desborough in the Invertebrate 
Department of the Leicester Museum under the writer’s charge. 
In conclusion the author wished to reiterate his remarks as to the 
importance for zonal purposes of this Gasteropod band of the 
Transition bed of the Middle Lias. 
The character of the fauna stamped it decidedly as purely littoral 
or coastal, whilst that of the beds below, containing as they did 
chiefly Brachiopoda and deeper-water Lamellibranchs and Cephalopods, 
pointed to their being of a more pelagic nature. 
It marked a change in the physical conditions which predominated 
at that period, and as such was rightly named a ‘ Transition bed,’ for 
the Upper Lias fauna was itself only a modification of it, with some 
differences of lithological composition in the strata and of species in 
the fauna which characterised it. 
Probably the inset of more littoral conditions took place between 
the formation of the thick encrinital seam mentioned above and that 
of the Transition bed. Certainly pelagic conditions, judging from the 
lithology and fauna of the beds below, seemed to come to a close about 
the time when this encrinital seam was deposited. 
The thickness of the strata and the fauna of the two sections, the 
one at Tilton as described by Wilson and the other as discovered at 
Billesdon Coplow by the writer, were, with some slight differences, 
due to local causes, more or less identical. 
VI.—Notrrs on THE Awnoctent VOLCANOES oF BASUTOLAND. By 
Rey. S. S. Dornan. 
ASUTOLAND is a high plateau between the Vaal and the 
Orange Rivers. It is the culminating point of the great plateau 
which fills the whole interior of the sub-continent. Upon this 
plateau, as a foundation, stand the great volcanic ranges, more than 
11,000 feet high. 
From the Caledon River to the edge of the great volcanic plateau 
is about fifteen miles. This plain is fairly level, and is interspersed 
with flat-topped mountains rising to 1,500 feet above the plain. 
These represent the original level of the country. The geology of 
the country is exceedingly simple. It is filled with the Stormberg 
series, lying nearly horizontal. The total thickness of these rocks 
