24n SCLERODERMI. 



D. Dorsal spine with four series of barbs. 



1. The front series are much closer together than the hinder series, and 

 formed by small barbs. 



24. Monacanthus hippocrepis. 



Balistes liippocrupis, Quo;/ Sf Gaiin. J^ui/. Uran. Zoul. p. 212. 

 Aleuterius variabilis, Richards. Voy. Ereb. ^- Terr. Fish. p. 07, pi. 53. 



figs. 1-7. 

 Monacanthus hippocrepis, Hollard, Ann. Sc. Nat. 1854, ii. p. 338; 



Steindachner, fiitzgsber. Ak. Wiss. IVien, 1868, Ivii. p. 1002. 



T). 35-37. A. 33-36. 



Skin rough, velvet-like. Old examples (16-17 inches long) with 

 four or six strong spines on each side of the tail, disposed in a double 

 scries, their points being directed forwards. In younger examples 

 (females?) these spines are comparatively smaller, with the points 

 directed backwards. Body elongate, its depth being two-fifths of 

 the total length (without caudal). Pectoral fin situated behind the 

 vertical from the orbit. Snout long, obtuse, with the upper profile 

 rather convex. Dorsal spine rather strong, two-thirds of the length 

 of the head, situated above the posterior half of the orbit ; it is 

 armed behind with a double series of small barbs, and in front with 

 a double series of small tubercles. Caudal fin subtruncate, with the 

 corners rounded ; dorsal and anal fins low. Ventral spine very 

 small, fixed. Brown, with undulated bluish bands on the snout 

 and along the lowerside. Two or three blue bauds or scries of 

 tipots along the back, one along the base of the anal. Side of the 

 trunk with a horseshoe-like black marking enclosing a yellow spot ; 

 or with a yellow blotch spotted with brown. Caudal fin with a 

 black crescent-shaped cross band. 



New South Wales. 



a. Fine specimen, 17 inches long. Sydney. From Mr. Krefft's 



Collection. 

 /'. Half-grown : stufli"ed. South Australia. 

 r, d. Adult : stuffed. Australia. 

 c. Half-grown: stuffed. Australia. From Mr. Gould's Collection. 



— Type of A. variahilis. 

 f. Half-grown. From the Haslar CoUectiou. 



25. Monacanthus knerii. 



Monacanthus (Paramouacauthus) knerii, Steindachner, Sitzgsber. 

 Ak. Wiss. Wien, 1867, Iv. p. 591. 



D. 35. A. 34. 



Skin velvety. Two rows of thin hook-like spines pointing back- 

 wards on each side of the tail. The height of the body is one-half 

 of the total length (without caudal). Snout with the upper profile 

 rather concave. Dorsal spine armed behind with a series of five 

 large barbs on each edge, and with a double series of more nume- 

 rous and smaller barbs in front. Ventral spine small, moveable, 



