LEPTOCEPHALIDiE. 145 



the throat. On the head there are a few pigmentary specks, and 

 the slightly-prominent eyes are silvery in their lustre. 



Total length 4-90 in. 



Height of body at the hinder third of its length . U-75 ,, 



Length from tiie point of the snout to the gill-openiug 0-51 ,, 



,, ,, to the anus . l'7;i ,, 



Thickness of the body . ' . 006 to 008 „ 



head 0-16 „ 



Length of the snout to the fore corner of the eye . 0-24 ,, 



,, of the oral orifice ...... 0*28 „ 



Genus 3. TILURUS, KdlUker. 



Distinguished from Leptocephalus by the rayless cuticular dorsal 

 fin, which begins at the occiput, by the muscular transverse fasci- 

 cular bands not forming, with their upper and under ends, inter- 

 rupted chevrons, pointing forwards. No anal fin. Anus situated 

 towards the end of the attenuated tail. Head small, and the 

 mandible scarcely longer than the upper jaw. Both jaws furnished 

 with pointed teeth. Gill-openings with distinctly-visible opercula, 

 situated near together under the throat. 



3. TiLURUs TRicHiuRus, Kaup, fig. 5. 



Leptocephalus trichiurus, Cocco. 



Tilurus Gegenbauri, Koll. Phi/s. Med. Gesellsc. in Witrzb. iv. Band. 



100. 



A very slim species, of the thickness of paper, which was first 

 described by Cocco. It was also collected by Dr. Gegenbaur in the 

 winter time at Messina. Charles Bonaparte and Troschel refer 

 trichiurus with doubt to O.vijstomus hyalinus of llafinesque, which 

 must be a perfectly distinct form, whose long outstretched jaws 

 have a likeness to those of a Bclone. The Prince cannot have seen 

 a trichiurus, and Troschel must have been unacquainted with the 

 works of l^finesque, otherwise they would not have fallen into this 

 error. Of the three specimens collected by Dr. Gegenbaur, one is 

 now in the Paris Museum, and it is from it that our sketch was 

 taken. There are in this some dots above the lateral line, which 

 occasionally run into transverse stripes. Fine points border the 

 body above and below, up to the extremity of the tail. In the 

 upper jaw there are seven small teeth near the corner of the mouth, 

 and four larger ones towards the taper-pointed snout. In the man- 

 dible there are eight teeth, all of nearly equal size. 



According to Professor Kolliker. the blood of trichiurus is colour- 

 less. The specimen described by that learned ichthyologist had the 

 following dimensions : — 



Total length 12kil in. 



Length from the point of the snout to the anus 10-91 ,, 



u 



