222 THE OCEAN. 



returning through the left auricle and ventricle, is 

 thrown into the right vodricle, and mixed with that 

 which is just brought from the body ; the mixed 

 blood being partly returned to the body through the 

 aorta, and partly sent to the lungs. But this is the 

 course only when the animal is breathing ; and as a 

 large part of its life is passed under water, this con- 

 trivance enables the circulation to go on under cir- 

 cumstances when breathing necessarily ceases. For 

 if no air enters the lungs, the blood cannot pass 

 through them; therefore, when under water, the 

 blood passing through the right auricle and ventricle, 

 is immediately sent by the aorta into the body with- 

 out any exposure to the air. Of course, as the blood 

 thus unrenewed would become more and more im- 

 pure, this could not proceed very long without loss 

 of life, and hence there is a limit to the period 

 during which the breathing may be suspended, when 

 the animal must come to the surface or die. 



Many of the fishes of these seas partake of the 

 brilliancy of colour with which the birds and insects 

 of the same sunny region are so lavishly adorned. 

 I have seen some of great beauty readily captured 

 with a hook from the deck of a vessel in shallow 

 water ; — such as the Yellow-fin (Spams synagris^ 

 Lixx.), which has its body marked with longitudinal 

 bands of delicate pink and yellow alternately; the 

 fins are bright yellow, and the tail fine pale crimson. 

 A larger species, which the seamen denominated the 

 Market-fish (Labrus anthvis, L.), is all over of a 

 silvery tint with a ruddy glow, the fins and tail 

 bright crimson ; this species has very large scales. 



