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Part III. — Fifteenth Annual Report 



developing them, — a feature of considerable interest. The larval marginal 

 fin, however, still joins the various parts to each other and to the tail. 

 The pectoral fins are large and fan- shaped, and the eyes are large and bluish- 

 silvery. Generally speaking, the whiting has more black pigment in the 

 postero-lateral region, both in this and in the previous stage, than the cod. 

 No ventral fins are present. 



At 12 mm. the dorsal and the anal fins are outlined, though not yet sepa- 

 rated from each other, and the permanent rays are more distinct in them 

 and in the caudal. Minute ventrals are now present, while the pectorals 

 form large mobile fans. The ventrals at this stage are in a line with the 

 posterior edge of the base of the pectorals, and thus differ from their 

 position in the adult. Groups of black pigment-corpuscles are distributed 

 along the base of the dorsal and the anal fins as well as over the brain, 

 and a similar series exists along the ventral median line of the abdomen. 

 Black specks also occur along the premaxillaries and the mandible. 

 The head is disproportionately large. Minute copepods are the most 

 conspicuous contents of the stomach at this stage. 



At 15 mm. the species is distinguished from the cod by the more 

 abundant distribution of black pigment-specks along the sides of the body 

 and on the fins, and by the greater length and diminished depth of the 

 first anal fin. The latter also readily separates it from the haddock. 

 At this stage many show a series of black pigment-specks over the silvery 

 lateral region of the abdomen from the dark dorsal arch (peritoneal) 

 downward. The pelvic fins have moved slightly forward. There is pro- 

 portionally less pigment when the ventral edge is surveyed than at the 

 9 mm. stage, but a more general distribution has taken place laterally. 



At 20 mm. the first anal fin has assumed the characters of the adult 

 organ, the body has considerably elongated, so that the head appears to 

 be smaller. The ventral fins have their origin distinctly in front of the 

 bases of the pectorals. A considerable aggregation of black pigment is 

 present along the dorsal margin, and all the median fins are dotted with 

 the same colour, especially the dorsals. Traces of the median ventral 

 black line are still visible. The black pigment-corpuscles along the sides 

 often present a more or less longitudinally linear arrangment. No scales 

 are developed. A minute papilla in the median line of the mandible 

 indicates a barbel. 



Shortly after this stage, viz., when about 32 mm. in length, a 

 tendency in the dorsal pigment to form separate touches is observ- 

 able ; the ventral surface of the abdomen becomes white. Besides 

 the former touches, a few distinct bars occur at the base of the tail. 

 The black pigment over the head, body, and fins has largely in- 

 creased, the sides being minutely flecked all over. The ventrals are 

 pale, their tips extend beyond the vent, and their bases are carried 

 still further forward. A minute barbel is generally present. Scales 

 are now developing, though the minutely granular areas which in- 

 dicate them are separated by considerable intervals. The distinction 

 between the young whiting at this stage, and the young cod of the same 

 length, is marked. In the whiting, the median dorsal fin is less abruptly 

 elevated than in the cod ; and the elongation of the first anal, w r ith the 

 shortening of the abdomen, are diagnostic in the whiting. The pigment- 

 specks closely cover the sides of the body in the whiting, as well as the 

 membranous webs of the dorsal fins, and are continued on the head. The 

 pigment at the base of the caudal rays is more distinct in the whiting, and 

 the lancet-shaped caudal end of the trunk is longer in this species. The 

 muscle-plates are coarser in the cod, and the surface has little of the 

 dappled silvery sheen of the whiting, The chromatophores in the cod are 



