MELVILL: THE PRINCIPLES OF NOMENCLATURE. 437 
The last seven years have likewise exhibited great acsiviy 
in various other fields connected with the Mollusca. Time 
does not allow me to more than allude to the new classification 
of the Pelecypoda, as proposed by Pelseneer, the revision of the 
Flelicide by Pilsbry, the completion of the Gastropodous 
section of Tryon’s ‘“‘ Manual of Conchology,” by the same 
author ; further researches into the deep sea fauna, by Dall and 
others ; the publication of the wolume of the Cambridge Natural 
History devoted to Mollusca, by the Rev. A. H. Cooke, a book 
which, it may be said, has not a dull page in it ; the “ Mollusca 
of Japan” as collected by R. E. C. Stearns, by H. A. Pilsbry; 
the first three parts of J. W. Taylor’s ‘‘ Monograph of the Land 
and Freshwater Mollusca of the British Isles”; and the second 
edition issued of L. E. Adams’ work on the same subject. 
So far as this country is concerned, there is no doubt that the 
existence and example of our two Societiest exercise a highly 
stimulating effect in this direction. 
And, as Bibliography is of paramount importance in these 
days of scattered papers and widely diffused literature on a 
given subject, Dr. Herbert Haviland Field’s * scheme of issuing 
a card catalogue of zoological literature, deserves more than a 
passing notice. 
The subject upon which I have elected to say a few words 
this evening is one which has been recently brought to our 
notice in a very prominent manner. A question which for some 
years, at all events in this country, had laid dormant, and by 
whose existing code of rules British zoologists and botanists had, 
since the revision in 1865, been content to abide, has again 
been brought to the fore, and discussions, often tending to 
exhibit great divergences of opinion, as well as articles in various 
+ For an almost exhaustive summary, shewing the great activity now being ex- 
hibited all over the world in the study of Malacology, refer to the two last Annual 
Addresses of Professor G. B. Howes, F.R.S., President of the Malacological Society 
of London, 1896-97 (Proc. Mal. Soc., vol. ii., pp. 57, 203). 
* c.f. Bouvier, E. L., Rapport sur le projet de réforme bibliographique de M. H. 
Haviland Field, Paris, 1895. 
