BY J. DOUGLAS OGILBY. 283 



forwarded at my request by the authorities of the South Austra- 

 Uan Museum for use in my work. It came from the estuary of 

 the Adelaide River, Northern Territory, and measure's 270 milli- 

 meters. I have great pleasure in naming it for Dr. Stirling, 

 F.R.S., of Adelaide, to whose kind offices I am mainly indebted 

 for the opportunity of describing this very distinct form. 



A. stirlingi belongs to the Hexanematichthys group, but may 

 readily be distinguished from A. auslralis by its much longer 

 barbels, wider dorsal plate, smooth humeral process, longer dorsal 

 spine and filamentous first ray, much larger anal fin, &c. 



PLOTOSID^. 



Endorrhis, gen.nov. 



Body elongate and strongly compressed, the skin nearly smooth. 

 Head subconical, much wider than deep, closely studded above 

 with small, wart-like papillae ; snout rounded and somewhat 

 declivous anteriorly. Mouth moderate or rather large, the upper 

 jaw projecting ; lips thick and papillose, the upper without 

 posterior filament; mental fold of lower lip small. Premaxillary 

 teeth conical, pluriserial, in two well developed patches, the outer 

 series enlarged; mandibular teeth in a broad, crescentic, narrowly 

 divided band, the outer series conical, the others granular and 

 unequal; vomerine teeth similar to the inner mandibular. Anterior 

 nostril on the inner side of the lip, with a well developed, grooved 

 tentacle. Barbels eight, two nasal, two maxillary, and four 

 mental, all slender. Eyes large, directed upwards and out- 

 wards, with continuous free lid. Gill-membranes partially united, 

 attached to the isthmus along the median line, leaving a more or 

 less restricted margin free; isthmus moderate; three posterior gill 

 arches with accessory branchial appendages ; seven to nine 

 branchiostegals ; gill-rakers well developed, smooth, compressed, 

 in moderate number. Axillary pore small. Tail not twice as 

 long as head and trunk. First dorsal with a pungent spine and 

 five or six soft rays, originating above the base of the pectoral; 

 second dorsal and anal well developed, continuous with the 



