Correspondence—Prof. T. G. Bonney. 47 
This conception of old drainage systems running parallel to 
the contours of the mainland, in Cumberland, Haddingtonshire, 
S.E. Ireland, Denbighshire, Flintshire, etc., when coupled with 
the warping movements necessary to explain the steep fall of the 
channels, sets the mind, no less than the land, awhizrl. 
BERNARD SMITH. 
THE GEOLOGICAL AGE OF THE CARRARA MARBLES. 
Sir,— Permit me to comment briefly on Dr. Du Riche Preller’s paper 
on the Carrara Marble District.1 It contains a quantity of interesting 
information, topographic and economic, but does little, in my opinion, 
to settle the question as to the age of those rocks or strengthen the 
position of the Italian geologists. I had their map with me in 
the autumn of 1889, and in regard to faults (which Dr. Preller 
considers to be almost negligible) wrote thus in my diary: ‘‘ In order 
to accept the geological succession they have indicated, we must 
explain the proximity of ordinary dark mechanically disturbed 
limestone (just like some of that at Spezzia) with lighter varieties to 
perfectly typical Carrara marble.” I was aware that the statuary 
marble is intercalated with marbles of inferior quality, but instead of 
finding any sign that the metamorphism was a result of pressure, 
maintain that, as shown by the microscope, that marble has escaped 
(as I stated) from the crushing which has affected its associates. 
As to ‘metamorphism’ and its effect on sedimentary rocks, I have 
been doing my best to study the whole question since about 1875, 
have spent much time and money in examining alleged passages 
from crystalline schists to comparatively unaltered sediments or 
intercalations of the two, with the invariable result that the evidence 
was never conclusive and very commonly worthless; in fact, I have 
not been able to discover any case (I have not restricted myself to the 
Alps) where a truly crystalline limestone, such as that of Carrara, is 
in stratigraphical sequence with a sedimentary rock to which a date 
‘can be assigned on the evidence of fossils, except in the case of 
contact metamorphism, which, so far as I am aware, is not exhibited 
in the Apuan Alps. Dr. Preller’s paper contains no evidence that he 
has made use of the microscope in studying these Carrara rocks, and 
as I know the vague use of the term ‘schist’ by many Continental 
and some British geologists I am unable to discuss his sections 
(Figs. I-LV) beyond saying that only one of them seems to demand an 
explanation, and this I think my past experience would enable me to 
supply. T. G. Bonney. 
RENE ZEILLER—MASTER PALHOBOTANIST. 
Sir,—In the current number of ature there is a short tribute by 
Professor Seward to Professor Zeiller, whose death this week in Paris 
we all deplore. I should like to add a word in token of the deep and 
lasting affection and reverence the great Palzobotanist inspired in his 
younger colleagues in many countries. 
*1 Grou. MAG., December, 1915, pp. 554-65. 
