61 KEPORT OF COMMISSIONER OF FISH AND FISHERIES. 



UDiformity in length and weight is less remarkable, however, than the 

 uniformity to be noticed in the shape and proportions of the members 

 of the same schools. Variations are chiefly observable in the thick- 

 ness and height of the body and the head and in the length of the fins, 

 especially the pectorals and the caudal. These dififerences in shape are 

 necessarily correlated with the activity and swiftness of the fish. Hence 

 the differences in the wariness, swiftness, and difficulty in capture, so 

 often referred to by old menhaden fishermen. 



As a general rule, according to Mr. Dudley, the fall fish are mixed 

 together without reference to fatness ; the latest ones, however, which 

 are supposed to be the main fish on their southern migration, are gen- 

 erally fat. 



Annual rate of growth. 



45. The shad is supposed to attain its full size in four years. Cap- 

 tain Atwood believes that the mackerel requires an equal length of time 

 in which to grow to its adult size of 17 or 18 inches. From studies 

 made in 1856, he concluded that they grew to the length of 2 inches 

 in about thirty days, and 4 inches in forty-five days, becoming CJ or 

 7 inches long before the October migration, the spawning having 

 taken place about the middle of May. In the second year they are the 

 ^' blinks ; " in the third, " tinkers ; " and in the fourth, full-grown mack- 

 erel. The menhaden must require three and perhaps four years to 

 attain adult size. Those which strike in at midsummer on the coast of 

 New England are probably hatched from the eggs spawned in the pre- 

 vious fall and winter. They are from 2 to 5 inches long. The second 

 year's growth is doubtless represented by the smallest sizes of the school- 

 ing fish, measuring from 7 to 10 inches, such as are catalogued in bottles 

 !Nos. 14045, 14846, and 18049. The third year's fish would be represented 

 by the abundant schools of fish of 12 and 14 inches, like those with 

 measurements specified in i^aragraph 43. The full-grown fish are the 

 immense ones taken in Maine and Massachusetts, measuring 36 and 18 

 inches. 



A most interesting circumstance is narrated by Mr. George W. Miles, 

 to whom I am indebted for many very valuable suggestions utilized 

 elsewhere. His observations were made in Long Island Sound. He 

 writes: — "In 1873 there were immense numbers of small fish, from 1 to 2 

 inches long, which appeared on the surface in the month of September. 

 Thousands of schools could be seen at a time and great numbers in each 

 school. They appeared to take possession of all the waters for the 

 remainder of that season. In 1874 these fish appeared again, late in 

 the season, and were about double the size they were in 1873. In 1875 

 they appeared again, much earlier, and in 1876 they came in about the 

 first of June, having increased in size and numbers. Apparently they 

 occupied the whole waters of the sound, so much so, that the larger fish 

 which frequented the sound were actually crowded out of it or left for 

 •other waters, and remained ofif Block Island at sea the remainder of the 



