PREFACE. 
XXXV11 
satisfactory knowledge of these various details from an examination of the 
Special Memoirs without great labour. 
It has appeared to me that, in the present state of science, the most useful 
and valuable form of summary of the work of the Expedition which I can 
attempt is a concise statement of the observations carried out, and of the 
scientific results obtained, at each of the several Challenger Observing Stations 
at sea. In the following pages, accordingly, summaries of this nature 
are presented in the belief that these detailed accounts of what has been 
accomplished at definite localities will not only prove of great assistance 
to all engaged in the study of oceanic phenomena, but will also serve as a 
guide to the future explorer who desires to fill up gaps in our knowledge, 
and to contribute to the rapidly advancing science of Oceanography. 
Many of the organisms captured m the dredge and trawl did not for 
various reasons reach the authors of the Special Memoirs. These were 
chiefly delicate animals, mutilated beyond specific identification by being 
hauled through the water from great depths, or by expansion of air 
and other gases relieved from great pressure. A complete list of the 
animals captured at each station was at the time, however, entered in the 
Station Book and in the journals of the naturalists together with notes as 
to the condition of the specimens when taken from the trawl. In the 
following summaries, the organisms now referred to are always reported in 
the station lists, in addition to those described in the Special Memoirs. 
In like manner the names and general character of the organisms taken 
daily and sometimes hourly in the surface and sub-surface toiv-nets were, 
after microscopic examination by the naturalists on board ship, entered in 
the note-books, along with numerous observations concerning the relative 
abundance of species and other matters of general or special interest. These 
remarks are now published, except where they have been rendered obsolete 
by subsequent discoveries. 
In the preparation of these accounts of the work done, and the results 
obtained, at the Challenger Stations, I have made use of the official log and 
note-books, the published reports, and my own journals. 1 have also had in 
my possession the manuscript journals of my colleagues the late Professor 
H. N. Moseley and the late Dr. R. von Willemoes-Suhm ; whenever I have 
made extracts from these, the authority has been given. 
(summary of results chall. exp. — 1895 .) 
/ 
