SUMMARY OF RESULTS. 
05 
known shallow-water species, at a depth of 680 fathoms, half-way between Iceland and 
the Faroe Islands.” 1 He mentions that he met with no Algae at depths greater than 200 
fathoms, the only vegetable structures occurring at great depths being Diatomacea, and 
he sums up as follows : — “ Basing my arguments on two facts which I venture to hope are 
unequivocally proved in the preceding pages, namely, that highly organized creatures 
have been captured in a living condition at depths vastly exceeding those to which 
animal life had previously been supposed to extend, and that their presence, where 
captured, cannot be regarded as an accidental or exceptional phenomenon, it has been 
my endeavour to establish the following important propositions : — 
“ I. The conditions prevailing at great depths, although differing materially from those Wallich’h 
which prevail near the surface of the ocean, are not incompatible with the maintenance Spa WS 
of animal life. Life. 
II. Assuming the doctrine of single specific centres to be correct, the occurrence of the 
same species in shallow water and at great depths proves that it must have undergone 
the transition from one set of conditions to the other with impunity. 
“ III. There is nothing in the nature of the conditions prevailing at great depths to 
render it impossible that creatures originally, or through acclimatization, adapted to Jive 
under them, should become capable of living in shallow water, provided the transition be 
sufficiently gradual, and hence it is possible that species now inhabiting shallow water 
may, at some anterior period, have been inhabitants of great depths. 
“ IV. On the one hand, tJie conditions prevailing near the surface of the ocean render 
it possible for organisms to subside after death to the greatest depths, provided every 
portion of their structure is freely pervious to fluid : on the other hand, the conditions 
prevailing at great depths render it impossible for organisms still constituted to live 
under them to rise to the surface, or for the remains of these organisms after death to 
make their appearance in shallow water. 
“ V. The discovery of even a single species living normally at great depths warrants 
the inference that the deep sea has its own special fauna, and that it has always had it 
in ages past, and hence that many fossiiiferous strata, heretofore regarded as having 
been deposited in comparatively shallow water, have been deposited at great depths. 2 
Many of Wallich’s opinions have been confirmed by subsequent researches, and 
altogether he must be regarded as one of the most industrious pioneers in the investi- 
gation of the deep-sea. 
The existence of a deep-sea fauna discovered by Wallich was soon established on con- 
clusive proof. In 1860, the telegraph cable between Sardinia and Bone in the Mediter- 
1 Wallich, op. cit., p. 151. 
2 Wallich, op. cit., pp. 154-155. In addition to the North Atlantic Sea-bed, Wallich is the author of many papers 
in scientific journals between the years 1858 and 1873, describing marine organisms and treating of various aspects of 
deep-sea investigations and controversies. 
