]04 ZOOLOGY OF THE VOYAGE OF THE BEAGLE. 



to say, however, to what extent the colours may have been altered by the spirit : 

 some of the scales also may have been rubbed oft'. 



Chromis facetus. Jen. 



C. supra virescenti-niger, lateribus pallidioribus : dorso modice arcuato ;fronteelevato, 

 rostro summo ante oculos paululum excavato : Umbo preoperculi ports quatnor con- 

 spicuis impresso : squamis latis, marginibus Uberis levissime ciliatis : spinis dor- 

 salibus quindecim, analibus sex: pinnis ventralibus longe acuminatis, ad ana/em 

 pertingentibus : pinna caudali subaquali. 



D. 15/10; A. 6/8; C. 16, &c. ; P. 14; V. J/5. 



Long. une. 5. lin. 9. 



Form. — Oblong-oval, very much compressed ; the back moderately elevated, and more curved than 

 the abdomen. Greatest depth a little behind the insertion of the pectorals, and contained 

 twice and three-quarters in the entire length: thickness about two-fifths of the depth. Fore- 

 head high : profile falling very obliquely, and slightly hollowed out in front of the eyes ; the 

 upper and under profile meeting at the mouth at nearly a right angle. Head contained not 

 quite four times in the entire length ; its own length and height nearly equal. Mouth small, 

 protractile : jaws about equal, the lower one, if anything, a little the longest : lips not very 

 fleshy. Maxillary rather slender, retiring almost entirely, when the mouth is closed, beneath 

 the sub-orbital, the anterior margin of which is slightly hollowed out, and somewhat sinuous. 

 Teeth in card in both jaws, forming a narrow band; the outermost row longer and stronger 

 than the others, especially the four or six middle ones in front, which are somewhat conical and 

 slightly hooked. Pharjmgean teeth present, but none on the vomeror palatines. Eyes rather 

 small, their diameter about one-fifth the length of the head ; high in the cheeks, and a little 

 nearer to the snout than to the posterior margin of the opercle : the space between broad, 

 equalling nearly two diameters and-a-half. Nostrils consisting of a single round orifice half-way 

 between the eye and the end of the snout. Preopercle with the basal margin short, and 

 forming a slightly obtuse angle with the ascending one, the margin of which is entire. Opercle 

 of a triangular form, broad at top, but narrowing off towards the bottom. Subopercle and 

 interopercle much developed ; their outer margins, taken together, rounded off nearly in a 

 semicircle. Branchial membrane quite free all round, unattached to the isthmus, and but 

 slightly emarginate. Snout, suborbital, jaws, and limb of the preopercle, naked ; but the 

 cheeks and rest of the opercular pieces scaly : the scales on the subopercle large. Four large 

 pores on the limb of the preopercle, preceded by three others beneath the lower jaw : similar 

 pores beneath the eye, and extending partially round it ; one on the crown of the head, and a 

 few smaller ones scattered about the snout; a large one just above the opercle, and another 

 higher up on each side of the nape. 



Scales on the body large ; about twenty-five or twenty-six in a longitudinal row, and 

 eleven or twelve in the depth ; broader than long, with the free edges very minutely ciliated, 

 the concealed portions with a fan of thirteen striae, and the basal margins with twelve distinct 



