296 PROCEEDINGS OF THE AMERICAN ACADEMY 



pectorals are elongated, and the greenish blue color of the body- 

 is limited to the dorsal regions, the sides being silvery ; a colored 

 belt, slightly greenish, extends along the base of the anal. In the 

 oldest pelagic specimen of young Motella (Plate YIII. fig. 3) the 

 barbel of the lower jaw is well formed, the anterior dorsal is higher 

 than the posterior dorsal, the ventrals are long fin rays equalling in 

 length one third of the length of the young fish, the greenish blue 

 color of the dorsal region is more intense than in the younger stages, 

 and extends in slightly lighter-colored diagonal bands across the 

 flanks ; the posterior part of the dorsal, of the anal, and the base of 

 the caudal are marked with small black pigment spots at the base 

 of the permanent fin rays. In this stage and in the one immediately 

 preceding (Plate YIII. fig. 2) the young fish make but little use 

 of their ventrals while swimming. The extremity of the caudal is 

 cut quite sharply at right angles to the longitudinal line, with 

 slightly rounded corners. At this stage the resemblance to Breg- 

 maceros is striking.* 



Gadus morrhua, Lin. 



(Plate VIII. figs. 4, 5.) 



The only other Gadoid of which I have found the young by fish- 

 ing on the surface is probably our common Cod ; when only 28°^°^ in 

 length it has in this early stage (Plate VIII. fig. 5) assumed all the 

 characteristic features of the genus. The only other young stage I 

 have seen is a young Cod measuring 20™°^ in length (Plate VIII. 

 fig. 4), which differed from fig. 2 in not having a barbel, and in having 

 the median fins still connected, although the three dorsal and two 

 anals were quite distinct. The pigment cells were not arranged to 

 form any definite pattern, but covered uniformly the dorsal region. 

 The breaking up of the continuous embryonic dorsal and anal into 

 separate fins is admirably seen in the stage represented in Plate VIII. 

 fig. 4. 



* Emery in his monograph of Fierasfer has also figured the pectorals of 

 the young Merlucius and Motella. There is still some uncertainty with regard 

 to the genus to which the specimens I have here referred to Motella belong ; 

 they may prove to be one of the species of Onus described by Collet. 



