138 THE SEA-SCORPION FAMILY. 



appear to be really in the protoplasmic layer enveloping the 

 yolk, and differ from those found on the body of the larva by 

 the fact that they are much branched, and often anastomose. 

 A good deal of individual variation in the amount of the 

 pigment exists, probably because some are hatched at a slightly 

 earlier stage than others. The larva, as in other species, hangs 

 in the still surface-water of vessels with the yolk-sac uppermost, 

 often with the head downwards. During the next three or four 

 days the pigmentation increases, the individual chromatophores 

 become branched, and the yolk-sac rapidly diminishes. 



One remarkable feature in the early stages of the grey 

 gurnard is the great development of the pectoral fins, as, 

 indeed, Cunningham also found in the red gurnard. This is 

 evident upon the second day, and it is accompanied by a 

 marked decrease in the region between them and the embryonic 

 ears. The snout also becomes prominent, and the mouth is open 

 from the first, although the gullet does not acquire a lumen till 

 later. 



At 5 days the little fishes have become active and are about 

 '165 inch long. The eyes have black pigment, with a greenish 

 lustre. The yellow colour is conspicuous about the head, the 

 yolk-sac, the pectoral fins, the anterior dorsal region and the 

 angle of the lower jaw. The black colour is found in abundance 

 at the base of the abdomen, and a few spots occur on the snout 

 and ventral border of the muscle-plates. The pectoral fins have 

 now developed into a pair of large fan-like paddles projecting 

 at right angles to the body and are concave backwards, forming 

 efficient organs of locomotion. 



During the following days there is an increase of the black 

 pigment and a still further hypertrophy of the pectoral fins. 

 The mouth still gapes widely, the gurnard being a fish which 

 essentially develops with its mouth open, a habit which gives 

 the larva a diagnostic appearance, and no doubt subserves 

 respiration to a great extent when combined with a rapid 

 forward movement of the body in the somewhat quiescent 

 water of the vessels in the laboratory. 



The last stage reached in confinement is about 3 weeks old ; 

 in this we note the huge pectoral fins, the yellow pigment on 



