74. SCOMBRID^ SCOMBER. 423 



pointed anteriorly. Moutli ratlier large; premaxillary not protractile ; 

 maxillary without supplemental bone; jaws wdth sliarp teeth, large or 

 small. Vomer and palatines toothed or not. Preopercle entire; opercle 

 unarmed. Gill-openings very wide, the membranes not united, free from 

 the isthmus. Gill-rakers usually long. Pseudobranchiai present, large. 

 A slit behind fourth gill. Branchiostegals 7. Dorsal fins 2, the lirst 

 of rather weak spines, depressible in a groove, the second similar to the 

 anal ; anal spines weak ; last rays of dorsal and anal usually detached 

 and separate, forming series of finlets ; caudal i)e(luncle extremely slender, 

 usually keeled, the caudal lobes abruptly diverging, falcate; veutral tins 

 moderate, thoracic, 1, 5. Vertebrae in greater number than in Carangidce, 

 the number more than 25. Pyloric coeca numerous. Air-bladder fre- 

 quently absent. Coloration metallic, often brilliant. General?; species 

 about 70. Fishes of the high seas, many of them cosmopolitan, and all 

 having a wide range. Most of them are valued as food-fishes. 

 (Scombridte i)t. aud Trichiuridce Y}t. Giiutber, ii, 349-373.) 



a. Finlets present; dorsal spines less than 20. (Scomhrhiw.) 



b. Spinous dorsal short (of less than 12 spines), remote from the second. 



c. Vomer and palatines with teeth; corselet obsolete Scomber, 213. 



ee. Vomer and palatines toothless; corselet well developed Auxis, 214. 



ih. Spinous dorsal long (of more than 12 spines), contiguous to the second. 

 d. Caudal keel present. 

 e. Corselet imperfect or obsolete ; teeth of jaws strong ; minute teeth ou 



vomer and palatines Scombeuomorus, 215. 



ee. Corselet developed. 

 /. Palatine teeth strong; vomer toothless; vertebra} normal. ..Sarda, 216. 

 ff. Palatine teeth villiform. 



g. Vomer with teeth; vertebrae normal, the lower foramina small. 



Orcynus, 217. 

 gg. Vomer toothless; abdominal vertebrte with the lower foramina en- 

 larged and a portion between the vertebrai proper and the hajmapophy- 

 ses developed in the form of a net-work or trellis Euthynnus, 218. 



213.— SCOIVIBER Liunajus. 



3Iac]cerels. 



(Linnaeus, Syst. Nat. 1758: type Scomber acombrus L.) 



Body fusiform, rather elongate, somewhat comj)ressed; caudal pe- 

 duncle slender, with two small keels on each side. Mouth wide, with 

 a single row of rather small, slender teeth in each jaw and ou the vomer 

 and palatines; maxillary slipping under the broad preorbital. Scales 

 very small, not forming a corselet. First dorsal of 7-12 feeble spines, 

 separated from the second by an interspace greater than the base of the 

 fin; second dorsal small, followed by 5-9 detached finlets; anal similar 

 to second dorsal, with similar finlets ; pectorals and veutrals small, the 



