114 NOTES ON THE REPRODUCTION OF TELEOSTEAN FISHES 



egg. A specimen of 7 mm. is fairly well preserved, at least on one 

 side, and while agreeing in pigment and conformation with the smallest 

 it can clearly be associated with the older forms, which, though 

 incompletely metamorphosed, are quite recognisable by the characters 

 of the adult. 



The specimen of 7 mm. (Fig. 1) is in its present state of preserva- 

 tion somewhat laterally compressed; the abdomen projects boldly below 

 the plane of the ventral contour of the caudal part of the trunk. The 

 pre-anal region, exclusive of the lower jaw, occupies two-fifths of the 

 total length. The snout is pointed, the lower jaw the longer, and both 

 jaws bear a single series of large recurved and rather widely set teeth. 

 The eye measures rather more than one-third of the length of the head. 

 The post-anal region is still elongate and rather slender, though 

 markedly deeper than in the vitelligerous stages ; its extremity is 

 slightly upturned by a trilobate hypural mass, beset with developing 

 rays, and similar rays are also present dorsally. The marginal fins are 

 mostly frayed away; the pectorals, also in bad condition, seem to have 

 been of moderate size. The eye, noted at the time of capture to be 

 blue, is now a dense black ; a patch of black chromatophores is present 

 on the top of the head, probably in the pia mater, and the roof of the 

 peritoneum (and in part its sides) is beset with black chromatophores. 

 From a short distance behind the anal region dorsal and ventral rows 

 of black chromatophores run back as far as the caudal peduncle, and a 

 few small black specks are present hypurally. Yellow pigment was 

 not observed at the time of capture ; it would not in any case be 

 visible in the preserved condition, unless very profuse or in large 

 corpuscles. 



Allowing for the difference in age, the specimen of 7 mm. agrees in 

 all respects with the late vitelligerous stage shown in PI. I., Fig. 7, 

 of my Irish paper. This figure was drawn from a larva of nine days, 

 4*88 mm. in length. With regard to the pigment the two specimens 

 are practically identical. 



Another specimen (Fig. 2) in fairly good preservation is 9'5 mm. 

 long. The pre-anal region is still shorter than the post-anal part, but 

 the distance between the anus and the tip of the urochord only 

 exceeds the pre-anal length by less than one-eighth of the latter. The 

 ventral contour of the abdomen is much less abrupt, though its hinder 

 part still projects somewhat from the caudal part of the trunk. The 

 pointed snout is nearly as long as the eye ; both jaws have teeth as in 

 the preceding stage, but relatively smaller. The tail of a larval fish of 

 some sort protrudes from the mouth, while the head can be detected far 

 back in the abdomen. 



The metamorphosis of the tail (of the mackerel larva) is advanced, 



