824 PROFESSOR W. C. M'INTOSH AND MR E. E. PRINCE ON 



May and beginning of June, preceding the arrival of the young cod of the stage formerly 

 mentioned, though perhaps not always. The characteristic features of the species, as 

 distinguished from the cod of the same size (1-g- inch), have already been indicated. 

 They consist of a deeper green hue all over, but especially anteriorly, and a much greater 

 development of black pigment-corpuscles both on the body, head, and fins. The eyes 

 also have a greenish hue, and these are proportionally larger than in the cod. The fins 

 throughout are duskier from the black pigment, and the three dorsal and anterior anal 

 are often marked by yellow pigment-grains. The pectorals in some show traces of two 

 broad arches of pigment, after the manner of other larval forms, such as the gurnard and 

 armed bullhead, though much less distinctly. The ventrals are well formed but small, 

 and show no special elongation of the outer rays. When specimens of this and the cod 

 are viewed side by side from the dorsum the difference in regard to pigment is striking, 

 the green cod being almost uniformly pigmented from the tip of the snout backward, 

 whereas the cod shows such chiefly on the tip of the snout and over the brain. More- 

 over, the snout in the young cod is decidedly longer and narrower, so that with the 

 distinction already noted in regard to the size of the eyes the whole facies differs. In 

 profile the gape of the cod is the longer, the mandible apparently being longer, and the 

 angle more pronounced. 



A curious feature was observed in those killed by a few drops of corrosive sublimate 

 (in acetic acid), viz., the closely adpressed condition of the first dorsal fin. 



In somewhat older forms, which are abundant in the rock-pools in July and 

 August, two varieties occur, viz., one of a pale though dull green along the dorsum and 

 upper lateral regions, the other of a dark olive-green in the same parts.* 



Gadus merlangus, L. — The eggs of the whiting abound in April and May, and 

 probably later. t They measure *0476 in., or about T125 mm. In an instance 

 in which they were fertilised at 3.30 p.m. on April 15, 1885, the germinal cap was 

 found at 6 p.m., and forty minutes afterwards the first furrow had appeared. At 9 p.m. 

 segmentation had proceeded beyond the eight-cell stage, and soon sixteen were outlined, 

 the nuclei in these being apparent at 9.40 p.m. On the second day, they were in the 

 multicelled stage, but no well-defined nuclear zone was visible, the latter being very 

 distinct on the third day. The blastoderm had largely extended on the fourth day, and 

 on the sixth the blastopore had closed, though Kupffer's vesicle had not yet appeared. 

 Lenses and otocysts were present. No pulsations of the heart occurred early on the 

 seventh day, but later intermittent contractions took place. Finely stellate chromato- 

 phores develop on the yolk-sac. \ On the eighth day yellowish chromatophores appeared on 



* Report on Trawling (1884), p. 360. 



t Day says the whiting "spawns in March not far from the shore," though what advantage the latter situation 

 gives is not stated. Mobius and Heincke observe that, according to Benecke, it spawns on the Prussian coast from 

 December to February, and in the Cattegat, according to Malm, from March to May. 



X Mr Cunningham considers that in the larval whiting the chromatophores are conlined to the body of the 

 fifth, and are absent from the marginal fin and the surface of the yolk. His diagnosis rests on specimens captured in 

 the tow-aet {Jour. Mar. Soc. Biol. Assoc, N.S., i.) In our experience the whiting is a form very early characterised by 

 in yellowish pigment, which invades the marginal fin. 



