FISHES. - MCCULLOCH. 173 



advance of the dorsal but reaching the vertical of the 

 ninth dorsal ray when adpressed; they are united by 

 membrane only at their bases; a short spine-like ray 

 precedes the first articulated one, which is simple while 

 the others are branched. The anterior anal rays are 

 branched and higher than the body above them, but those 

 following them are simple and decrease in length until 

 towards the posterior third of the tail where they become 

 gradually longer. A short interspace separates the last 

 anal ray from the caudal, but the two are apparently 

 united by membrane. Upper caudal ray long and 

 branched, the others decreasing in length downwards. 



Colour. Whitish after long preservation, the scale- 

 pits margined with brown on the upper parts. Eye and 

 gill-covers black. Posterior third of the anal fin and the 

 caudal fin with brown margins. 



Described and figured from the holotype, 545 mm. 

 long. 



Variation. Two para types, 535 and 595 mm. long, 

 have twelve rays in the dorsal fin, and only five or six 

 rays in the caudal. 



Affinities. This species belongs to the typical section 

 of the genus Halosaurus, characterised by the presence 

 of scales on the upper surface of the head, and by having 

 the scales on the lateral line not or but little enlarged. 

 Its very long pectoral fins distinguish it from most of 

 its allies, but it is very similar to H. oweni from Madeira 

 and the Atlantic, differing principally in having a longer 

 head as compared with the trunk. 



Locality. Great Australian Bight, south from 

 Eucla, 350-450 fathoms; 14th May, 1913. 



Family 

 Key to the Australian Genera. 



A. First dorsal with several long rays. 



B. Anal without a detached or semi-detached portion 



anteriorly. 



C. An outer row of strong teeth in each jaw followed 



by a narrow band of smaller ones; scales very 



small. Lotella. 



CC. Teeth subequal in size, in bands; scales larger. 



D. Premaxillary teeth in a single broad band on 



each side. Physiculus. 



DD. Premaxillary teeth divided into two series on 



each side by a groove. Austrophycis. 



