72 ACANTHOPTERYGII. 



Grenus, 16 — Helotes, Cuv. 



BrancUodegcds six. Eyes of moderate size. Cleft of mouth rather small, jaws nearly equal in front. 

 Preopercle serrated : opercle with weak spines. The outer row of teeth m the jams having a small lohe on each side : 

 palate edentulous. Dorsal fin single, not deeply notched, having twelve spines ; anal with three. Scales small, ctenoid. 

 Air-vessel divided iy a constriction into an anterior and posterior portion. Pyloric appendages in moderate numbers. 



Geographical distribution. — Ceylon* ? to the Malay ArcHpelago and beyond. 



Sixth group — PristipomatidSB. 

 Branchiostegals from five to seven. Preopercle serrated or entire. Mouth moderately protractile. 

 Teeth in the jaws. Three anal spines. Air-vessel destitute of any constriction. 



Genus, 17 — Peistipoma, Cwv. 



Oenytremus, Genyatremus, Anisotremus and Pristocantharus, Gill : Hmmulopsis, Steind. 



Branchiostegals seven : pseudobranchioe. Body oblong, compressed. Eyes of moderate size. Cleft of mouth 

 horizontal : gape not very -wide : premaxillaries moderately protusible : jaws of nearly equal length : a central 

 longitudinal and deep groove below the symphysis of the lower jaw, and two small open pores under the chin : no 

 barbels. Preopercle serrated : opercle with indistinct points. Teeth in the janjos villiform without cam/ines : palate 

 edentulous. Dorsal vnth from eleven to fourteen spines, and sometimes ha/ving a deep rwtch between the last two : 

 anal with three spines. Vertical fins scaleless or only so along their bases. Scales ctenoid and of moderate or small 

 size, present on the head, including the preorhital and lower jaw. Air-vessel simple, destitute of aivy constriction. 

 Pyloric appendages few. 



Geographical distribution. — All tropical seas and Ukewise found in the Mediterranean : tlie young of the 

 Indian species are often taken in backwaters. 



Uses. — ^Paif as food but not much esteemed : the air-vessel in some places collected as isinglass. Many 

 breed about April or May. 



SYNOPSIS OF SPECIES. 



1. Pristipoma stridens, D. Yi-\-s' -^- h ^- ^- Vi-wf- Purplish on the back, becoming white on the- 

 abdomen. Three golden bands along the body and a dark mark on the upper third of the opercle. Red Sea, 

 along the Meckran coast to Sind. 



2. Pristipoma olvvaceum, D. ^, A. ^, L. r. f^. Olive-grey, the head glossed with purple : a black 

 mark on the opercle. Beloochistan and Sind. 



3. Pristipoma furcatum, D. ^^^, A. -g^-^, L. 1. 65-60. Silvery, with six sinuous blackish-brown bands, 

 three of which are above the lateral-line : a dark mark on the opercle : spinous dorsal with three rows of brown 

 spots and a dark edge : upper half of dorsal dark, and a band along the anal. Seas of India to the Malay 

 Archipelago. 



4. Pristipoma hasta, D. t^-yj-, A. y?g^, L. 1. 45-50. Pour or five lines of dark grey along the sides, 

 sometimes coalescing and forming bands : two or three rows of spots along the dorsal fin. Red Sea, East coast 

 of Africa, seas of India to the Malay Archipelago and beyond. 



5. Pristipoma Commersonii, D. if, A. -f-, L. 1. 50. Sinuous rows of black dots over upper two-thirds of 

 body, and several rows along the dorsal fin. Madras. 



6. Pristipoma maculatum, D. fTT)-T4) -^^ !"> ^- ^- 52-56. Greyish, becoming white beneath : a black 

 band over the nape, and sis black blotches along the side, three above and three below the lateral-line, not 

 forming bands but placed like squares on a chess board. Red Sea, Bast coast of Africa, through the seas of 

 India to the Malay Archipelago and beyond. 



7. Pristipoma Dussumieri, D. if, A. f, L. 1. 50-54. Greyish, becoming Kghter below : two golden 

 lateral bands : fins with dark edges. Seas of India. 



8. Pristipoma guoraka, I). Wm, A. y-t> ^- 1- 45-47. Silvery, an olive spot on the opercle. Seas of 

 India to the Malay Archipelago. 



9. Pristipoma operaula/re, D. ^\, A. f-, L. 1. 57. Silvery, vnth a black blotch at the posterior-superior 

 angle of the opercle : upper half of the body with numerous black spots, sometimes forming undulating bands : 

 a dark spot at the base of each dorsal spine and ray. East coast of Africa to Sind. 



1. Pristipoma stridens, Plate XVIII, fig. 8. 



Soicena stridens, Porsk. p. 50. 

 Perca stridens, Bl. Schn. p. 87. 

 Pristipoma svmmena, Guv. and Yal. v, p. 260. 



Pristipoma stridens, Riippell, N. W. Ksche, p. 122, t. 31, f. 1 ; Giinther, Catal. i, p. 300 • Klunzinffer 

 Pische Roth. Meeres, Verb. z. b. Ges. Wien, p. 732. ' ^ ' 



* In the list of the Acanthopterygian fishes of Ceylon, prepared hy Dr. Giinther (Sir E. Tennent's Nat. Hist, of Cevlon 1861 

 p. 360), is Eehtes polytoemia Bleeker, as that species = Ther(vpon guad/riUneatus, I conclude that Dr. Giinther's species which 1 have 

 not seen, may be identical. ' 



