770 DEPTHS OF THE OCEAN 



42 cm. long, taken at Station 41 in 1365 metres. We see here 

 a great number of rings, perhaps twenty m all, but these rmgs 



are in many respects 



_ ■""' essentially different 



,^^^>o from the annual rings 



' ;^ :' '; in the scales of boreal 



/'■ ; fish. In the latter the 



V . central rings are as a 



\ rule very large, the 

 ^v subsequent rings be- 



coming narrower as the 

 fish grows older. If 

 the rings in the scale 

 of Bathygadus signify 

 periods of growth, 

 these wouldseem to be 

 of a peculiar character, 

 cm. in length from the 



Fig. 564. 



Scale of Canthariis lineatus, Montagu (White). 



Length of fish, 42 cm. 



Fig. 564 is the scale of 



coast banks of Africa, 



Cantharus lineatus, 



taken in shallow water 



at a high temperature. 



This scale also shows 



rings which are very 



distinct, especially to- 

 wards the periphery of 



the scale. 



In Fig. 565 I have 

 represented a scale 

 from a surface fish, 

 Polyprioii americanus, 

 49 cm. in length, 

 taken in the surface 

 waters at Station 56. 



In the scales of 

 all these fishes, taken 

 under such various 

 conditions, we observe 

 peculiarities of struc- 

 ture, resembling the • 1 1 r 

 rings produced by the periodicity of growth m the scales ot 

 fish from boreal waters. There seems thus to be every reason 

 for subjecting the growth of the scales and other organs of 



Fig. 565. 



Scale of Polyprion atnoHcatins, Bl. and Schn. 



Length of fish, 49 cm. 



