290 THE COD FAMILY. 



abdomen silvery with reddish-brown contents. Blackish pig- 

 ment occurred along the dorsum and sides chiefly the former. 

 The eyes were silvery bluish. The rays of the moderately 

 elongated ventrals were dull yellowish, and thus in contrast 

 with their general blackish dusting. The circulation was 

 complete and in full activity. In contrast with the young 

 four-bearded rockling of exactly the same length, the eye is 

 brownish in the preparation instead of bluish-black and silvery, 

 a condition, however, to which no weight need be attached. No 

 pigment occurs on the body, but the ventral fins are brownish 

 throughout, and much shorter than in the other species. The 

 snout is less blunt and less heavy than in the four-bearded form, 

 a feature partly due to its diminished diameter. 



At 16'5 mm. a large barbel occurs at the tip of the mandible, 

 and short processes at the anterior nostrils, as well as traces of 

 the labial barbels. The pectoral fins are considerably elongated, 

 though they have not reached as far back as the tips of the 

 ventrals. The body is silvery with the exception of a small 

 portion posteriorly, and with dark pigment at the dorsum. The 

 tail is symmetrical, so that the bend of the notochord would 

 seem to be temporary. A young parasite (Caligus) had fixed 

 itself over the cardiac region. 



At 24 mm. (Lochmaddy, August) the specific characters are 

 evident, viz., the presence of the five barbels, the longest being 

 that on the chin, and the last-developed the pair on the lips, 

 the character of the head, and the greater depth of the region 

 immediately in front of the caudal fin. Day states that the 

 young of this form is brown with blue eyes, but not a few of 

 the length just mentioned and larger have the steel-blue of 

 the dorsum and the silvery sides so characteristic of the four- 

 bearded species. Perhaps, however, Dr Day alludes to a later 

 stage, and variations may occur in regard to the assumption of 

 the adult characters. The first ray of the dorsal is not much 

 thickened in these bluish-silvery pelagic forms. 



When 28 g 5 mm. long, on the 9th June, an example showed 

 that at every stage variation occurs, since the labial barbels 

 were just indicated and no more. The dorsum was not so 

 deeply pigmented as in some, but the whole fish was silvery. 



