250 



In the specimens of 15 m.M. length we captured, the coloration 

 was almost identical with that of the young fishes just described, 

 only a little more intense, and the occiput a little more darkly 

 coloured. There foUows a gap in our observations. The youngest 

 trachinus vipera we captured, that had allready all the characters 

 of the adult animals, was 33 m.M. long. But the gap may be 

 easily filled with the observations of Mc. Intosh and Masterman. 



Trachinus draco. As I mentioned before, the larvae of trachinus 

 draco before the absorption of the yolk-sac are very unlike those 

 of Trachinus vipera, their ventral fins being small and uncoloured, 

 and the form and coloration of their body differing much from 

 that of the lesser weever. 



But soon after the yolk has been absorbed and the oil-globule has 

 disappeared the little fishes begin to assume the weever characters. 



In the specimen figured in fig. 4 on Plate I of only 4 m.M. 

 length the form of the body is still very much like that of the 

 oldest larval forms figured in my former paper. The head and 

 especially the lower angle of the jaw has become more prominent, 

 with an upward slope of the mandible. The mandibles and maxillar 

 are more developed, the coloration of the trunk is still much the 

 same as it was before ; the peculiar weever character however is 

 shown in the now rather strongly developed ventral fins, with 

 distinct finrays and a dark pigmentation between the rays espe- 

 cially in the outer part of the fins. The pectoral fins are quite 

 colourless, the dorsal and ventral finfold are still quite embryonic, 

 and the dorsal finfold still reaches almost to the end of the snout. 

 There is as yet no tracé of the spines of the first dorsal fin. 

 The notochord is not yet bent upwards at its end, but the finrays 

 of the tail are already more developed at the ventral side of the 

 tail than at the dorsal. Patches of black pigment occur along 

 the ventral side of the body behind the vent, the abdomen over 

 the gut shows black stellate pigmentspots ; the black spot behind 

 the eyes has disappeared, but on the occiput a large stellate 

 pigmentspeck has become visible. 



