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The little larva is therefore very raucli like the larvae of Tra- 

 chinus vipëra of the same age. It can, however, be distinguished 

 at once from this ferm by the smaller head and by the series of 

 black pigmentspots along the ventral side of the tail, beginning 

 somewhat behind the vent. In Trachinus vipera there are no pigment- 

 spots but for one pigmentcell at the base of the caudal fin (fig. 1). 



The specimen figured in fig. 4 was captured in the month of 

 August on St. H. 9 (near Hook of Holland) in midwater (at a 

 depth of 10 metres) '), together with a lot of the older postlarval 

 stages of Trachinus vipera and Trachinus draco. 



The next stage, drawn iu fig. 5, 4,3 m.M. in length, was 

 captured at the same spot at a depth of 20 metres. It shows the 

 first traces of the development of the first dorsal fin, the ventral 

 fins are somewhat more developed than in the foregoing stage, 

 the mouth is armed with small larval teeth. The pigmentation of 

 the larva is exactly the same as in the foregoing figure. The 

 jaws are assuming already the peculair form, so distinctive of the 

 adult greater weever. 



The larva figured in fig. 6, 7,5 m.M. in length, captured at 

 the same spot as the larva just described, shows some marked 

 differences. The head is assuming the characters distinctive of 

 the greater weever. When we compare it with tbat of the larve of 

 trachinus vipera drawn in fig. 1, of almost the same age, we see 

 that the form is entirely different, smaller in relation to the body, 

 the mouth turned upwards, and that the two forms may be 

 distinguished at once. The spines on the operculum are visible. 

 The finrays have been formed, the notochord is bent upward to 

 form the caudal fin, the first dorsal fin is set off from the second 

 dorsal; the pigmentation of the little larva is still allmost exactly 

 the same as in the larva of fig. 5. By this pigmentation we are 

 able therefore to distinguish at once the larvae of trachinus draco 

 from those of trachinus vipera where the tail remains almost 

 entirely uncoloured. 



1) With the „Scheibrutnetz." 



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