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tered between, the oil-globule being covered with some 5 or 6 

 pigmentcells. 



In the larva 5 days after hatchiug, with the yolk-sac almost 

 entirely absorbed, the distribution of the pigment is still almost 

 the same as in the newly hatched larva; only the scattered 

 pigmentcells on the trunk have arranged themselves in a doublé 

 row on the ventral side of the body from the vent almost to the 

 end of the tail. The thick pigmentspot at the middle of the tail 

 has diminished in size, but is even in the larvae with almost no 

 tracé of a yolk-sac left still visible. The patch of pigment near 

 the vent has increased in size and is very conspicuous. The eyes 

 are pigmented. No tracé of the pelvic fins are yet to be seen. 

 The breastfins are colourless. 



Trachinus vipera. The eggs of the lesser weever present (as was 

 allready well known) an entirely different aspect, the yolk being 

 provided with a large number of small yellow oil-globules, which 

 diminish in size during development and disappear before the 

 embryo is hatched. 



The issuing larvae are characterised by the abuudance of black 

 pigment on the trunk, and by the large conspicuous deeply pigmented 

 pelvic fins, which were already developed in the embryo before 

 hatching, and give the little larvae a very striking appearance. 



Of the postlarval stages of the lesser weever the features were 

 only superficially described. They are recognisable at once by the 

 peculiar character of the broad and deeply pigmented pelvic fins, 

 by their trunk and dorsal part of the head being covered with 

 black and yellow pigment and the tail being entirely devoid of 

 pigment. It was mentioned that the first spines of the dorsal fins 

 are already strongly developed in specimens of about 7 mM. 



Of the postlarval stages of trachinus draco nothing was said, 

 for although I had cuptured several older larvae which might 

 possibly belong to this species, the uecessary intermediate stages 

 were missing, and so I was not quite sure of the diagnosis. 



Two years ago the Institute bought a „Scherbrutnetz" of the 

 Heligolaud pattern, that enabled us to fish for larvae swimming 



