Holt and Caldeewood — Report on the Rarer Fishes. 373 



when the denticulations of the posterior border are numerous and small, and the 

 extreme lateral margins show traces of a secondary pair of keels ; or may be feeble, 

 the posterior denticulations being few and large ; or may exhibit a condition 

 between those described. 



Teeth in upper jaw with a single sharp cusp, either narrow, the length of 

 cusp much greater than the base, or broader, the outline of the cusp forming 

 nearly an equilateral triangle. In the lower jaw the cusp is either narrow and 

 almost perpendicular, or broader, with a well-marked lateral deflection. A median 

 tooth usually present ; absent only in extreme varieties. Colour uniform, either 

 brown, inclining towards mahogany colour, or very pale, from chalky-white to 

 blackish-grey. White specimens become a dull brown after immersion in alcohol. 

 Iris black. Pupil clear emerald-green. 



Dr. Vaillant, in his remarks on the " Talisman " and " Travailleur " collec- 

 tions (o/?. cit., p. 69), pointed out, for the first time, that those forms which had 

 hitherto been described as C. squamosiis and C. Dumerilii are in reality only varieties 

 of one species, to which the older name, C. sqimmosus, must, of course, be applied, 

 while C. Dumerilii must be treated in future as a synonym. The amalgation of 

 the two forms is due to the occurrence, amongst the specimens which came under 

 Vaillant's notice, of examples exhibiting intermediate characteristics. Vaillant 

 has, unfortunately, not given any detailed information in regard to the particular 

 features which influenced his decision ; but the specimen examined by us gives 

 in itself sufficient proof of the truth of his assertion, and we have accordingly 

 constructed a diagnosis of the species which includes both forms. 



There exists, unfortunately, some confusion as to the nomenclature of the 

 two so-called varieties. C. squamosus, Gm. Linn., is founded on tlie Ccntro2)hore 

 ecailleux of Broussonet ; but Vaillant, who has re-examined Broussonet's type 

 specimen (a somewhat mutilated head), states that it is not the C. squamosus of 

 later authors — notably Glinther, in the " Catalogue of the Fishes in the British 

 Museum," vol. viii., p. 422 — but the C. Dumerili of Johnson. 



The sjjecimen examined by us bears in almost every particular the features of 

 the variety, i. e. the C. squamosus of Giinther and other late authors. In the vital 

 particular of teeth, however, we find that, while exhibiting the broad cusps of 

 the lower jaw strongly deflected outwards, in a manner quite in keeping with the 

 other features of C. squamosus, Giinther, a median tooth is present in both jaws. 

 Median teeth are one of the most important distinguishing features of the type- 

 species, the Centrophore ecailleux of Broussonet and C. Dumerili of Johnson. "VVe 

 therefore second the amalgamation of the two forms which was px'oposed by 

 Vaillant for reasons which probably are not less important than those noticed by 

 that author. 



The two varieties, taking the extreme development of the characters which 



