32 THE VOYAGE OF H.M.S. CHALLENGER. 



Ceratodus miolepis, Gtkr. 



Irregularities in the arrangement of scales do not appear to be scarce in both species 

 of this genus, and occur chiefly in the median line of the back or abdomen, some of the 

 scales of the median series being either subdivided or confluent with those of the 

 adjoining series. The specimens collected by the naturalists of the Challenger Expedition 

 belong to the smaller-scaled species, which, as far as is known at present, is confined to 

 the Mary Eiver. In some twenty specimens from that river, which passed through my 

 hands, the normal number of longitudinal series was found to be twenty-one, although 

 in a few of them, as also in one of the specimens of the Challenger collection, one more or 

 less may be counted on account of the irregularity mentioned. The Burnett Ceratodus 

 {Ceratodus forsteri) is more rarely brought to Europe. I have seen three specimens 

 only, which had eighteen rows of scales ; but Dr A. B. Meyer mentions a specimen in 

 which he counted twelve scales below the lateral line, or nineteen altogether (Ann. and 

 Mag. Nat. Hist., 1875, vol xv. p. 368). 



Oligorus macquariensis, C. V., Eiver Mary, near the village of Tiaro. 



Ctenolates amhiguus, Eich., Queensland, lat. 27° 9' long. 144° 0'. 



Datnia amhigua, Richards, Yoy. "Erebus" and "Terror," Fish., p. 25, pi. xix. 

 Ctenolates macquariensis, Gthr., Proc. Zool. Soc, 1871, p. 320, pi. xxsiii. 



TheraiDon unicolor, Gthr., Queensland, lat. 27° 0' S., long. 144° 0'; Eiver Mary, near 

 the village of Tiaro. 



Ambassis mariamis, n. sp. 



D. 7/j^rYi, A. -^, L. lat. 28, The height of the body is two-fifths, or in young 

 specimens less than two-fifths of the total length (without caudal), the length of the 

 head one-third. The diameter of the eye is two-sevenths of the length of the head and 

 two-thirds of that of the postorbital portion. PrsBorbital strongly serrated. Scales on 

 the middle of the trunk much larger, and those on the nape much smaller than the 

 remainder. Lateral line interrupted below the end of the spinous dorsal, the pores of the 

 posterior portion being rather indistinct. The second dorsal spine is as long as, or some- 

 times a little longer than, the third, and one-fom-th of the total length (without caudal). 

 The third anal spine is longer than the second, but considerably shorter than the second 

 of the dorsal. A narrow, silvery, longitudinal streak along the middle of the tail ; the 

 membrane between the second and third dorsal spines blackish. Caudal fin not coloured. 



We liad altogether some fair sport, and a good opportunity of seeing the natives and making ourselves familiar 

 with the character of Australian scenery and the Austrahan fauna. I am sure aU our party wiU long remember our 

 months' excursion with pleasure. 



Most of the fishes in the Queensland list were procured during this trip. Those marked lat. 27° 9' long., 144° 0' E., 

 were collected by Mr Lyon at his station about 400 miles inland of Brisbane, and was sent by him to Mr Murray. 

 — C. Wy. T.] 



