IN THE SOUTH-WESTERN DISTRICT. 139 



from a female in the Aquarium in IMarch, were found by the same 

 author to measure 1"05 to 1"15 mm. The larva, hatched from a tow-net 

 egg, is figured. It has an irregular series of dorsal and ventral black 

 chromatophores from the head to near the extremity of the tail. 



Observations in January, 1898, show that large examples of G. Inscvs 

 contained ripe ova, of which the largest measured 1"13 mm. one hour 

 after extrusion into sea- water, on the 10th of the month. This dimen- 

 sion would be subject to further increase, but the eggs were not fertilised 

 and died. Ova of corresponding dimensions, giving rise to larvse re- 

 sembling Cunningham's figure, first appeared on the 4th January, 1898, 

 from grounds known to be frequented by G. luscus. It is therefore 

 reasonably certain that Cunningham's identification is correct, and we 

 have therefore associated with G. luscus those forms which in date, 

 dimensions, and larval characters appear to sufficiently fulfil the 

 required conditions. It will be seen that these ova, observed by 

 Mr. Scott, occurred from the 28th January to the 6th February. The 

 diameter ranges from "90 to 1"10 mm., so that the eggs are rather small 

 as compared with those obtained from parents in January of the 

 present year. The smallest ova I have as yet found are derived from a 

 female twelve inches long (20th Jan., 1898), and measure "98 mm. after 

 twenty-two hours' immersion in sea- water. If I am right in supposing 

 that the smaller members of the species spawn later and have smaller 

 eggs than their larger sisters, the small size of some of the 1897 tow-net 

 ova is accounted for. The dimensions do not serve to distinguish them 

 from eggs of G. minutus, but such evidence as I have points to a rather 

 later spawning season for that species. Ten females, examined on the 

 12th January, 1898, were still far from ripe. 



In every case when the development of the embryo was followed, the 

 ova entered as G. litscus can be associated with the larva that appears 

 to belong to this form. It is characterised by a rather regular double 

 series of dorsal and ventral black chromatoplwres, extending from the 

 head to the neighbourhood of the caudal extremity. In larvte of a 

 few days old the supra-cephalic ampullation, common to several if 

 not to all Gadus larvae, is well developed, Onhj black pigment is usually 

 visible, but I am able to affirm the presence of yellow chromatophores 

 also, an observation which explains existing discrepancies in the de- 

 scriptions of various authors of other Gadus larvae. 



In the larvae (of G. luscus) which I have observed no coloured chroma- 

 tophores can be made out as long as the specimen is in full health and 

 vigour ; but a greenish or yellowish refraction is noticeable, often very 

 faintly, on the salient parts, such as the front end of the yolk or the 

 head. I have not succeeded by any manipulation of the light in 

 detecting the presence of coloured chromatophores, and as a similar 



NEW SERIES.— VOL. V. NO. 2. K 



