CXXXIV REPORT OF COMMISSIONER OF FISH AND FISHERIES. 



were noted, including numerous food-fislies. Important additions to 

 our knowledge of the fauna of the Antilles were made, and valuable 

 data concerning the fishery possibilities of the island were gathered. 



As soon as the vessel returned, the collections were sorted and dis- 

 tributed for study to prominent specialists, a number of important 

 groups being assigned to assistants of the U. S. National Museum. 

 Collections of birds, plants, and land forms generally, incidentally 

 obtained by members of the Commission, were transmitted to the 

 National Museum. It is the intention to bring together in one volume 

 the scientific results of the expedition, and it is expected that the work 

 will be a valuable contribution to the knowledge of the aquatic fauna 

 and flora of Puerto Rico and the West Indies. 



STUDIES OF SPECIAL FISHES. 

 VARIATIONS OF MACKEREL. 



Recent investigations by Mr. Walter Garstang, of the marine bio- 

 logical laboratory at Plymouth, England, have shown that not only do 

 the mackerel {Scomber scomhrus) inhabiting our coastal waters difi'er 

 strikingly in structural details and color from those found on the shores 

 of Great Britain and Ireland, but also that the mackerel of the British 

 coast have peculiarities among themselves by which the fish from one 

 section may be distinguished from those of another.* Similar investi- 

 gations as to the mackerel of the western Atlantic would be of great 

 scientific value and would have an important bearing on the problems 

 connected with artificial propagation, commercial fishing, and the 

 international relations of the fishery. 



Mr. M. C. Marsh, scientific assistant in this division, was assigned 



to this investigation, and spent a part of May and June, 1899, in the 



examination of fresh mackerel in the New York markets. Owing to the 



almost complete failure of the southern spring mackerel fishery, it was 



impossible to secure for this inquiry more than a few fish from the 



southern grounds, but satisfactory series of mackerel from the New 



York and southern New England shores were obtained for examina 



tion. Hon. E. G. Blackford, of New York, extended the facilities of his 



Fulton Market office to the Commission's representative, and in other 



ways showed his interest in the work. The inquiry will be actively 



pushed during the next fiscal year, although several seasons may be 



required to collect sufficient data from all parts of the United States 



and Canadian coasts. 



VARIATIONS OF SHAD. 



From an economic and fish-cultural point of view, as well as from a 

 purely biological standpoint, it is of interest to determine whether the 

 shad which frequent the waters of the entire east coast of the United 

 States belong to one race or whether different hydrographic areas have 

 runs of shad which may be distinguished by structural and color fea- 

 tures. Fishermen and fish-dealei s often profess to distinguish by super- 



* Journal ol' the Maiiue liiological Association, 1898. 



