248 



of the body. The hindpart of the body was entirely without 

 pigment, and nearly invisible in a living state. The first dorsal 

 fin was very darkly coloured (d'un noir intense). A lateral view 

 (not very elucidative) of this specimen is given in fig. 74. 

 Of the earlier postlarval stages as yet nothing is known. 



Soon after the yolk has been entirely absorbed, the young 

 Trachinus vipera lose the peculiar intense black pigmentation of 

 the foremost and middle part of the body that made them so 

 conspicuous during the later larval stages. Only the coloration of 

 the black pelvic fins remains. The first tracé of its beginning to 

 assume the weever character is the developing of the first four 

 finrays in the embryonic dorsal fin. The rays of the tail begin to 

 develop, the tip of the chorda begins to curve upwards and soon 

 the form is reached that is figured in fig. 1 Plate I. In the little 

 larva, 6 m.M. in length (+ ^4 inch) the only pigment visible 

 is the intense black coloration of the large pelvic fins, a stellate 

 black pigmentcell at the base of the tail and one somewhat 

 farther on, and two or three black pigmentcells on the dorsal 

 side of the gut. But for these cells and the black eyes the larva 

 is colourless. 



The spines on the operculum are already strongly developed, 

 at the dorsal and ventral sides of the myotomes the finray-buds 

 begin to show themselves, the first four spines of the dorsal fin 

 already much more developed than the others, in its form and 

 especially in the height of the body behind the large head the 

 young animal is showing itself already a true Lesser Weever. 



In specimens of 7 m.M. the first spines of the dorsal fin are 

 already strongly developed, the other finrays have appeared, but 

 the coloration and general aspect of the larva remain the same. 

 The head becomes still larger in relation to the colourless and 

 slender body and tail, the spines of the operculum and the 

 preaperculum beconie still more strongly developed, the embryonic 

 fiufolds become converted into the real fins, and soon the stage 

 figured in figs. 2 and 3 on plate IV is reached. 



