140 NOTKS ON THE REPRODUCTION OF TELEOSTEA.N FISHES 



tinge is often visible in the blastodermic mound of a fish-egg, and 

 certainly is not due in that case to pigment, I concluded that only black 

 pigment was present. However, it so happened that a larva injured 

 itself on the stage of my microscope, and during the development of 

 the usual morbid symptoms I became aware of the presence of minute 

 yellow chromatophores, rather closely set over the greater part of the 

 skin. 



It appears therefore that yellow chromatophores, though present in 

 large numbers, cannot (in all cases, if at all) be detected in healthy 

 larvse. So far as my experience goes, a larva of G. luscus with con- 

 spicuous (i.e. contracted) yellow chromatophores would be exceptional. 



In the case of G. minuhis, I have seen and described Irish tow-net 

 specimens, almost certainly belonging to the species, in which no yellow 

 chromatophores were visible. The larva of this form was first de- 

 scribed from the Mediterranean by Eafiaele, its correct identification 

 being beyond doubt. Only black pigment was observed ; and larvoe 

 observed by myself at Marseilles agree in this respect with Eaffaele's 

 description and figure ; while, though only tow-net material was studied, 

 the identification was, from the known fauna of the district, beyond 

 doubt. I have seen similar larvre at St. Andrews, yet M'Intosh's, the 

 only British specimens hatched from artificially fertilised ova, are very 

 conspicuously decorated with yellow chromatophores. (M'Intosh and 

 Masterman. PI. X., Figs. 1-3.) The absence of yellow pigment from 

 Mediterranean larvae may be actual as well as apparent, since a regional 

 variation may very well exist in this particular. As to British 

 forms, the figures (1 and 2) of M'Intosh's youngest larv?e appear to 

 have been drawn from unhealthy specimens, and the yellow chroma- 

 tophores appear to be contracted. It is possible, though I do not 

 insist on the suggestion, that in perfectly normal British larvfe of 

 G. minntus the yellow chromatophores may be too diffusely expanded 

 to be conspicuous. 



The larvae of the cod and haddock have been so extensively studied 

 that I do not think that yellow chromatophores, if present, could have 

 failed to attract observation, for the other characters of these two species 

 are sufiicient to ensure their distinction (if occasionally coloured). Larvae 

 of the whiting have been described by M'Intosh and Prince, from 

 artificially fertilised eggs, and by myself, from tow-net material, as 

 profusely adorned with yellow. On the other hand Cunningham {Journal, 

 N.S., i., p. 46, Fig. 34) makes no mention of yellow pigment in a larva 

 which he refers to the whiting. It is possible that the yellow pigment, 

 which seems to be usually conspicuous in this species, may be occasion- 

 ally invisible as in G. luscus. Cunningham's ova, from which the 

 supposed whiting larva was derived, measured 1-23 mm. in diameter, and 



