Waite. — New Zealand Fishes. 387 



Triarcus, gen. nov. 



Differs from Gonostoma in Laving only three gills, the dorsal fin not 

 behind the ventrals, and the adipose fin low and very long. 



The following is a description of the larger of the two examples : — 



D. 9 ; A. 26 ; V. 8 ; P. 15 ; C. 22 + 10 ; Sc. circ. 26 ; Sc. tr. 5+6. 



Length of head, 3-7 ; height of body, 4-3 in the length ; diameter of 

 eye, 2-8 ; length of snout, 3-5 ; and interorbital space, 4-6 in the head. 



Head compressed ; mouth small, sub vertical ; lower jaw the longer ; 

 the maxilla extends to below the middle of the eye ; teeth in the jaws small 

 and uniform, extending the whole length of the maxilla ; no teeth on the 

 vomer or palatines ; no pseudobranchite. Gills, 3 ; gill-rakers long and 

 slender, 29 on the first arch, 22 of which are on the lower limb. 



Body compressed. The dorsal fin commences midway between the 

 hinder edge of the eye and the root of the caudal ; the length of its base is 

 equal to the diameter of the eye, and its longest ray (the second) is one- 

 fourth greater. The adipose fin is low, but very long, its base being greater 

 than that of the rayed fin, from which it is separated by a space nearly 

 equal to its own length. The anal is long, more than twice the length of 

 the dorsal, and it lies entirely behind that fin ; its longest rays are of similar 

 height, and those of both fins gradually decrease backwards. The ventral 

 is placed immediately beneath the anterior ray of the dorsal, and extends 

 to the anal when adpressed. The length of the pectoral is equal to the 

 longest dorsal ray. The caudal is forked, and the depth of its peduncle is 

 less than the diameter of the eye. 



Scales large, cycloid, and moderately adherent. There are about 25 in 

 the longitudinal, and 5 or 6 in the transverse series. 



The dark (steel-blue) colour of the dorsal surface is sharply defined from 

 the silvery sides. The area surrounding the photophores is also very dark 

 in colour. 



Adopting the nomenclature appUed to the MydophidcB, the distribution 

 of the photophores may be described as below: — Preorbital : 1, midway 

 between the eye and the end of the snout. Suborbital : 1, behind the 

 maxilla. Opercular : 2 on the opercle, and 6 beneath the gill-cover. 

 Mandibular : 2 pairs on the mandible — 1 near the symphysis, and the other 

 much further back ; 5 pairs on the isthmus. Thoracic : 5 pairs behind the 

 opercle and parallel to its border, 12 pairs in advance of the ventral ; also a 

 series of 9 on each side, placed much higher and in the same horizontal 

 line as the suborbital and lower opercular pores. Ventral : 6 pairs, the 

 second one being below the level of the others. Anal : 25 pairs, a break 

 between the 17th and 18th, occurring over the last anal ray ; the anterior 

 pore of the anal series is over the first anal ray, and placed high ; the second 

 pore is also higher than the following ones, which form an even and regular 

 line. Caudal : none. 



Length, 61 mm. 



4. Centrolophus huttoni, sp. nov. 



Mr. A. D. Goodall, of Kaikoura, recently advised me that he had caught 

 a large sunfish, which was accompanied by a number of " pilots." He 

 sent me two of the latter, and wrote as follows : " Kespecting the sunfish, 

 I noticed its back fin just awash with the water, and when it lay over on its 

 side I steamed up and harpooned it. It must have weighed several hundred 

 13*— Trans. 



