1. TRACHTPTERUS. 303 



pies the middle third of the length of the head, near to the upper 

 profile. Interoperculum nearly as large as the operculum ; the gill- 

 opening extends to the vertical from the eye. Pectorals very short ; 

 ventrals about as long as the body is high. The anterior six dorsal 

 rays are elevated ; the others have a rough surface, and there is a 

 small spiny tubercle at the base of each of them. Eight of the caudal 

 rays are inserted on the upper part of the extremity of the tail, 

 forming a separate caudal lobe, obliquely directed upwards ; the 

 enter rays of this lobe are longer and stronger than the intermediate 

 ones, and have their surface rough ; the other caudal raj^s are short, 

 pointing backwards. Lateral line with a series of small bony shields, 

 each of which is armed with a spine; a double series of small 

 tubercles along the cutting edge of the abdomen. The lateral line 

 gradually descends towards the lower profile, which it reaches at the 

 extremity of the tail, where it becomes confluent with the lateral line 

 of the other side ; there is a spiae at the point of the junction of the 

 two lateral lines, with a process directed forwards, and another di- 

 rected backwards. The vent is situated a httle before the middle of 

 the length. Silvery, with three blackish spots on the back, and 

 sometimes with one or two paler ones on the side of the abdomen. 

 Fins rose-coloured. 



Typical specimens nine to twenty inches long. 



A specimen in the Collection of the College of Surgeons, nine 

 inches long, and named Trachypterus cristatus, probably belongs to 

 this species. It is without any spots, and has 150 rays in the dorsal 

 fin. 



5. Trachjrptenis altivelis. 

 Kner in Wien. Sitzungsber. 1859, xxxiv. p. 437. taf. 1. 



B. 6. D. 7 I 190. A. 0. C. 6/4-6. P. 11. V. 7. 



The greatest height of the body is above the ventral fins, equal to 

 the length of the head, and one-seventh of the total. Form of the 

 head as in T. tcenia. Eight teeth in the upper, and six in the lower 

 jaw. The anterior dorsal rays elevated ; the longest of the second 

 dorsal fin are not much lower than the body ; dorsal rays rough, and 

 there is a small spine at the base of each of them. Form of the 

 caudal fin and tubercles of the skin as in T. tcenia. Silvery, with 

 three large round black spots below the dorsal fin ; a fourth near 

 the abdominal edge, a little behind the first on the back. 



Valparaiso. 



The typical specimen is in the Vienna Museum. 



6. Trachypterus iris. 



Taenia falcata, {Imperato) Aldrov. iii. c. 30. p. 371. 



prima, Emdel. xi. cap. 17. p. 326 ; Bay, p. 39 ; Artedi, Sijnon. 



p. 114. 

 Ichthyopolis romanis Cepole dicta, Willughhy, p. 116. 

 Cepola iris, Walb. Artedt, iii. p. 617. 

 Epidesmus maculatus, Ranzani, Opusc. Scient. iVItal. ii. p. 133. 



