£92 Correspondence—H. L. Hawkins. 
If another name is called for, as, I think, it is, the form syenoid 
(derived from felspathozd syenite, but it can also be interpreted 
literally as “ syenite-like ’’) has an advantage over an entirely new 
name, inasmuch as it preserves the connexion with syenite and so 
imposes no fresh burden on the memory. Also it is only one of a 
whole series of terms which are all constructed on the same principle ; 
and finally it is brief and euphonious. 
I grant that the matter is a trivial one, yet I am convinced that 
in the judicious use of prefixes and suffixes we shall find the best 
solution of the difficulties of nomenclature. If this is “‘ perversity ”’, 
then I am guilty and unrepentant. 
S. J. SHAND. 
UNIVERSITY OF STELLENBOSCH, 
GEOLOGY DEPARTMENT. 
February 9, 1921. 
“THE RELATIVE AGE. OF CONCRETIONS.”’ 
Sir,—There is cne paragraph in the interesting and suggestive 
paper by Mr. W. A. Richardson (in the March GroLocGicaL 
MaGazineE) over which I feel constrained to join issue with the 
writer. In the course of arguments in favour of subsequent forma- 
tion of the concretions surrounded by “ conformable”’ lines cf 
stratification, and against the hypothesis that consolidation 
pressure ’’ produces such effects, he quite rightly assumes that the 
latter would require the occurrence of similar “ conformity ”’ 
around fossils and other contemporaneous objects offering special 
resistance. And then he states (p. 118) “* But it certainly is not”’. 
My experience (and surely that of every worker in the Chalk) would 
compel me to emend that sentence by omission of its last word. 
Itis hard to find a specimen of Micraster or Echinocorys in the nodular 
parts of the planus-zone that is not considerably damaged by 
‘* slickensiding”’, precisely similar to that affecting the nodules 
themselves. While fully prepared to believe that these particular 
nodules are truly “ subsequent” (although the fossils cannot be so), 
I cannot accept this particular argument. It is always unsafe to be 
5 
‘“‘ certain’’ about a negative. 
H. L. Hawks. 
‘ UNIVERSITY COLLEGE, READING. 
March 9, 1921. 
