REPORT on the MARINE DIATOMACEHA# of the 
Ee MBC DistRicr. 
By Dr. H. StotterrotsH, M.A. 
[Read 8th February, 1889.] 
In the present condition of our knowledge of the Dia- 
tomacee, it is impossible to give a scientific arrangement 
of the genera and species. All the attempts that have 
hitherto been made are based on artificial systems, that 
must some day be superseded, and so I have thought it best 
in this catalogue, which I have prepared for the Liverpool 
Marine Biology Committee, to do what most of the recent 
writers on the subject have done, viz. place the genera and 
species in alphabetical order. This makes the list easy to 
consult, and in no way precludes its being used by those 
who adopt an artificial system of reference. One of the 
best of the artificial systems is that proposed by Professor 
H. L. Smith, and which will be found in Dr. Van Heurck’s 
‘Synopsis of the Diatomacee,”’ p. 37 of the text. 
The great difficulty that surrounds the study of the 
Diatomacee, is that so many writers seem to look upon it 
as necessary to give new names to even the commonest 
species, and the transference of well known forms from 
one genus to another, adds not a little to the complication. 
Different localities and conditions give rise to variations, 
which in many cases have been made to constitute new 
species. I have endeavoured to avoid this, and I hope that 
the following list will be of some use to those who are 
working at this subject. Very few lists of the Diatomacez 
of particular districts in this country have been published. 
They are as follows— 
1. “New Forms of Marine Diatomacee of the Firth of 
2 
