Halosaurus ovenii. From plate 40 of Oceanic Ichthyology by G. Brown Goode and Tarleton H. Bean, published 1896.
From http://www.photolib.noaa.gov/historic/nmfs/images/big/figb0617.jpg

Source: https://commons.wikimedia.org/wiki/File:Halosaurus_ovenii.jpg

Halosaurus ovenii, also called the Oven's halosaur, is a deep-sea fish in the family Halosauridae. It is found in the eastern Atlantic where it is widely distributed in tropical and subtropical waters along both coasts. In the Mediterranean, H. ovenii is considered rare. It can reach up to 60 cm in length.
Order: Notacanthiformes
Family: Halosauridae
Genus: Halosaurus
Species: Halosaurus ovenii Johnson, 1864