APR 10 1899 



[ 235 ] 



On the Variation, Races and Migrations of the 

 Mackerel {Scomber scomber). 



By 



Walter Garstang, M.A., F.Z.S., 



Naturalist in charge of Fishery Investigations under the Marine Biological Association ; 



late Fellow of Lincoln College, Oxford. 



INDEX OF CONTENTS. 



Introduction ...... 



I. The Method of Investigation .... 



II. The Characters Investigated .... 



III. Particulars concerning the Consignments of Mackerel Investigated 



IV. Size of the Mackerel Investigated .... 

 V. Sex (Numerical proportions, Secondary Sexual Characters) 



VI. Number of Transverse Bars .... 



VII. Shape of Transverse Bars .... 



VIII. Dorso-lateral Intermediate Spots .... 



IX. Number of Finrays in First Dorsal Fin 



X. Correlation between Spottiness and Number of First Dorsal Finrays 



XI. Number of Finrays in Second Dorsal Fin 



XII. Number of Dorsal Finlets .... 



XIII. Correlation between Second Dorsal Fin and Dorsal Finlets 



XIV. Summary of Evidence concerning the Races of the Mackerel 

 XV. The Migrations of the Mackerel .... 



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Pmir Men savoir les choscs il en faut savoir le detail. 



De La Rochefoucauld. 



Introduction. 



The present investigation was undertaken at the invitation of H.M. 

 Treasury, in consequence of an application to the government from 

 H.M. Inspectors of Irish Fisheries for a scientific investigation into the 

 life-history of the mackerel. The problem to the solution of which 

 the inspectors attached particular importance was the relation to one 

 another of the spring and autumn schools of mackerel which regularly 

 visit the Irish coasts. In the spring a multitude of large fish approach 

 the south and west coasts of Ireland to breed. In the autumn schools 



NEW SERIES. — VOL. V, NO. 3. Q 



