XV. 
SKETCHES OF THE CHARACTERISTIC DEEP-SEA TYPES. — FISHES." 
Tux collections of the earlier deep-sea expeditions consisted 
almost exclusively of invertebrate animals, and it was not until 
the publication of the “ Challenger ” results that any large num- 
ber of deep-sea fishes became known. The first extensive con- 
tribution to our knowledge of the vertebrate inhabitants of the 
great depths of the sea was made by Dr. Giinther of the British 
Museum, in 1878. He printed in the “Annals and Magazine 
of Natural History” a series of papers containing descriptions 
of some species of fishes which had been obtained by the “Chal- 
lenger.” 
The deep-sea fishes, as a whole, although distinguished by 
marked peculiarities, consist of types not wholly unfamiliar to the 
ichthyologist. Many of the characteristic abyssal families have 
representatives in the inshore faune, less strongly specialized 
perhaps than their allies in the abysses, but still structurally 
the same. Others had in former years become known, from 
dead individuals which floated to the surface or drifted ashore. 
The latter have usually been designated as .“ pelagic forms," 
and until the existence of a deep-sea fauna was revealed, the 
problem of their origin was much less intelligible than it 1s now. 
Even now, the distinctions between the inhabitants of deep 
water, those of the middle depths, and those of the surface 
strata of mid-ocean, are not strongly defined. Such are the im- 
perfections in the methods of trawling and dredging, that the 
naturalist, when he has sorted out the fishes from his nets after 
1 I am indebted to Professor Goode East Coast of the United States by Goode 
and Dr. Bean for notes upon the Fishes. and Bean, based upon the collections of 
'The figures are taken from a Memoir the * Blake " and of the U. S. Fish Com- 
preparing on the Deep-Sea Fishes of the mission. 
