COMPARISONS OF OTOLITHS. 295 



contrast between a shallow fresh-water type and a deep sea-water 

 type. It is interesting to note that JElurichihys gronovii is 

 closely allied to Arius gagora, whose otolith is shown on Plate I. 

 fig. 19. 



Beryx splendens lives in very deep waters, and Myripristis 

 murdjan, another of the Berycidte, lives in water near the shore, 

 therefore much shallower, but it likewise has a large otolith. 

 Here, then, they follow a family type irrespective of the depth 

 at which they live. The more commonly known Flat-fishes 

 (the Pleuronectidce) all have comparatively large otoliths, and 

 of other fishes that live on the bottom of the sea, the Weever 

 (Trachinas draco), Uranoscopus scaber, and the Gobies, each have 

 large otoliths. We have here several different kinds of fishes fre- 

 quenting the bed of the sea, and each supplied with a fairly large 

 otolith. For a comparison we must go to the Blenny family, 

 many of which live on the bed of the sea, yet they all have 

 small otoliths. Compare that from a Blennius gattorugine, Plate I. 

 fig. 4, with one from a Gobius paganellus, fig. 5. These two fishes 

 varied but little in size ; their mode of life is fairly similar on 

 the bed of the sea, yet the otolith of the Goby is manifestly 

 the larger of the two. The Cod (Gadus morrhua), living and 

 feeding near the bottom of the sea in deep water, has a large, 

 solid otolith, and so has the Tile-fish, Lopholatilus chamcsleonticeps 

 (Plate II. fig. 1), which lives at the bottom of the Gulf Stream, 

 hundreds of miles from the east coast of the United States of 

 America. The Scombrida, the Mackerel family, living in the 

 surface strata of the deep sea where they find their prey, have 

 small otoliths. Plate I., figs. 1 and 2, show otoliths of this 

 family. The Sparidce have, as a rule, large otoliths (one from 

 a Sea-Bream, Pagellus centrodontus, Plate I., fig. 11, shows this) ; 

 the otolith from a Ballan Wrass, Labrus maculatus (Plate I. 

 fig. 12) is much smaller, and strikingly different in shape. The 

 two fishes, however, frequent much the same localities and 

 depths ; both are littoral fishes. 



Plate L, figs. 13, 14, 15, illustrates three different kinds of 

 otoliths from the family Salmonidce. The first of the three (fig. 13) 

 is the otolith of a Smelt (Osmerus eperlanus), fig. 14 shows that 

 of a Salmon (Salmo salar), and fig. 15 that of a Grayling (Thy- 

 mcdlns vulgaris). Their modes of life are different ; the Smelt 



