602 REPOKT ON THE EGGS AND LARV/E OF TELEOSTEAN FISHES 



These measurements were taken within thirty-six hours of the 

 larva hatching. The total number of larvae hatched and measured 

 was forty-four, and their sizes varied between 2'3 and 376, but in 

 all other cases than those given in the above table the larvse could 

 not be referred to particular eggs. 



In most of the eggs when they reached their final stages a yellowish 

 tinge was distinctly visible, and in some cases faint yellow pigment 

 spots could be seen, and in all the larvae produced either a yellowish 

 tinge could be detected or yellow spots were visible just as in the 

 larvas hatched from eggs attributed to G. merlcmgus, but very faint. 

 The degree of yellowness, however, was not the same in all cases, 

 and in some the pigment spots only became visible when the larvae 

 were moribund, where before there had only been a faint yellow tinge. 

 In these cases the spots were discernible all along the body and on the 

 head, and in a few cases several spots could be made out on the yolk 

 sac and at the extreme anterior end of the dorsal fin. 



With regard to those larvae which when healthy showed pale pigment 

 dispersed as in G. merlcmgus, I did not have enough to ascertain cer- 

 tainly whether they only arose from the larger eggs. I find one record 

 of an egg 1"09 which produced such a larva 3"2 mm., and I had other 

 such larvffi 312, 312, 312, 3-45, 3-2, 3-2 mm. in length. I kept four 

 of these larvae on April 12th, hatched from eggs taken on the 9th, and 

 also one larva of G. mcrlmigus ; and on April 14th the merlcmgus larva 

 still showed strong yellow pigment spots, whereas the other three 

 larvae (one had died) had lost their distinct chromatophores and only 

 showed a yellow tinge. It is on account of these larvae that I said 

 that possibly some of the eggs of G. merlangus were indistinguishable, 

 and though from the size of the one egg given and from the different 

 appearance of the larvae they may be some other species than the 

 whiting, there is, of course, nothing at present to draw conclusions 

 from. 



Heincke and Ehrenbaum (Uier und Larven von Fischen der deutschen 

 Bucht, 1900, pp. 120 and 170) describe the pigmentation of the em- 

 bryo pollack as being similar to that of G. cvglcjinus and possessing 

 black pigment only, arranged in a line down each side to the tail, and 

 they distinguish G. luscus from G. pollachius by the presence of yellow 

 pigment in the former. Now the pollack is an extremely abundant 

 fish in the neighbourhood of Plymouth, and it would be strange indeed 

 had I not obtained a few eggs at least of this species. Yet the only 

 Gadus egg I have had which showed no trace of yellow was the egg of 

 G. morrhuci. 



Of course, it must be borne in mind that the tow-nets examined have 

 all, or nearly all, been taken within three or four miles of the shore, 



