124 " ENDEAVOUR " SCIENTIFIC RESULTS. 



A. elongating is distinguished from all other species of the 

 genus by its comparatively naiTow form. It has also thirteen 

 rays in the right ventral, its scales are mostly cycloid, and its 

 type of colouration is different from the others. 



Loc. Investigator Strait, South Australia, or the area south 

 of Kangaroo Island. 



AMMOTRETIS TUDOR i, gp. nor. 

 (Plate xxvi.) 



1). 77-82 ; A. 54-58 ; P. 10-11 ; V. dex. 10; V. sin. 6. Depth 

 Wo-lTi), head i|-4^ in the length from the upper jaw to the 

 hypural. Eye equal to or less than its distance from the tip of 

 the upper jaw, and 4^-5 in the length between that point and the 

 end of the operculum. Upper pectoral l-lj 8 o in the head : the 

 lower only a little longer than the eye. Caudal equal to or a 

 little shorter than the head. Longest dorsal and anal rays about 

 If in the head. 



Upper side mostly covered with ctenoid scales which become 

 almost cycloid towards the middle of the body in large specimens ; 

 011 the lower side they are nearly all cycloid, sometimes ctenoid 

 towards the edges. They extend over the greater part of all the 

 rays except those of the pectoral and the anterior dorsal and 

 ventral ones. The lateral line is nearly straight between the tail 

 and the pectoral, but is slightly curved or inclined upwards over 

 the latter fin. Its origin is on the same level as the upper 

 margin of the upper eye. There are about eighty or ninety 

 poi-es, and the same number of scales along its length as far as 

 the hypural, and from thirty-five to forty on either side of it 

 across the widest part of the body. 



Eyes on almost the same level, or the upper a little in advance 

 of the lower. Maxillary not reaching backwards to the orbital 

 margins ; lower lip with a row of fringed tentacles. Nostrils 

 tubular, the anterior of both sides with posterior lobes. Teeth 

 similar to those of A. rostratus, in a narrow baud on the lower 

 sides of each jaw. Gill-rakers of the first arch reduced to minute 

 tubercles. 



Dorsal commencing on the tip of the rostral hook, the anterior 

 rays free, simple, and serrated ; the thirteenth to fifteenth rays 

 are longer than those immediately following them. Left pectoral 

 much smaller than the right, the first ray with a large fleshy 

 tubercle at its tip. Right ventral in a line with and joined to 

 the anal, the anterior rays somewhat similar to those of the 

 dorsal. Middle caudal rays longest, the margin rounded or 

 obtusely pointed. 



