396 Dr. H. Hicks—Pre-Cambrian Rocks of Wales. 
are as complex as the molars. Prof. Marsh considers this form 
closely related to the recent Tapir and standing in ancestral relation- 
ship to it. 
The distribution of the genus Tapirus in Post-Pliocene times in 
America appears to have been very general, and remains of Tapirs 
are recorded from many of the Southern and Western States. 
In conclusion, we may summarize the following points in the 
evolution of the Tapir, and the relationship between the American 
and Kuropean species of Protapirus: 1. True Tapirs make their first 
appearance in America in the Lower or White River Miocene; this 
formation is higher stratigraphically than that in which Protapirus 
(P. priscus) occurs in Europe. 
2. The American species, Protapirus obliquidens, is in about the 
same stage in the evolution of its premolars as that of the P. Douwvillei, 
from St. Gérand-le-Puy in France. 
3. Protapirus priscus of the Phosphorites is a much higher 
developed type than its probable contemporary in America, namely, 
Isectolophus annectens. 
4. In contrast with the other Perissodactyla of the White River 
formation, the premolar teeth of Protapirus are simple in structure, 
and have not assumed the pattern of the true molars as in the 
recent Tapir. 
d. We cannot agree with M. Filhol, that the genus Protapirus is 
the same as the American genus Hyrachyus. We believe these 
genera are entirely distinct. 
II].—Tue Pre-Camsrian Rocks or WaAtEs.! 
By Henry Hicxs, M.D., F.R.S., F.G.S. 
N a recent article on the Pre-Cambrian Rocks of the British Isles 
in the Journal of Geology, vol. i., No. 1, Sir Archibald Geikie 
makes the following statement: ‘‘There cannot, I think, be now 
any doubt that small tracts of gneiss, quite comparable in lithological 
character to portions of the Lewisian rocks of the North-West of 
Scotland, rise to the surface in a few places in England and Wales. 
In the heart of Anglesey, for example, a tract of such rocks presents 
some striking external or scenic resemblance to the characteristic 
types of ground where the oldest gneiss forms the surface in Scot- 
land and the West of Ireland.” To those who have followed the 
controversy which has been going on for nearly thirty years between 
the chiefs of the British Geological Survey and some geologists who 
have been working amongst the rocks in Wales, the importance of 
the above admission will be readily apparent; but as it is possible 
that some may be unable to realize what such an admission means 
in showing geological progress in unravelling the history of the 
older rocks in Wales during the past thirty years, a brief summary 
of the results obtained may possibly be considered useful. It is 
now twenty-nine years since it was announced by Mr. Salter (at 
the meeting of the British Association, 1864) that during researches 
1 Paper communicated to the Geological Congress, Chicago, August, 1893. 
