REPRODUCTION OF THE MACKEREL. 297 



the fish and put them in alcohol, marking the date, aa I considered this time the middle of the 

 spawning season. (By the 10th of Jane the fish had all deposited their spawn, and they then 

 prom-drd to the grounds whore they expected to meet with better food in order to fatten and 

 recruit. The spawning takes place at a depth of from five to fifteen fathoms.) Thirty days after 

 I went out in the bay and found any quantity of schools of little Mackerel which were, I should 

 think, about two inches long, though their length might have been a little less. I took a number 

 of specimens and put them in alcohol, marking the date. Twenty-five days later I procured 

 another lot of them which had grown to double that size. I don't mean to imply that they were 

 twice as long, but twice as heavy. I put them also in alcohol, marking the date. The first time I 

 subsequently went to Boston I called on Professor Agassiz and gave him the specimens. He said 

 that he had never before been able to ascertain these facts so clearly and so well, and that he was 

 very much pleased with them. I watched the growth of these young Mackerel all along, and I 

 saw them grow considerably from month to month, so much so that the same fall, in the latter 

 part of October, I caught some of them with a very small mesh net and found they had grown to 

 a length of six and a half or seven inches. I kept a small quantity of them, split, salted, and 

 packed them, in accordance with the Massachusetts inspection law, as No. 4's, and since Mackerel 

 were then scarce and very high in price, I sold them for as much as $6 a barrel." 



"Much yet remains to be learned in regard to the spawning season of the American Mackerel," 

 writes Professor Baird, "and little more is known of this except in regard to the European 

 variety. It is, however, well established by the researches of Sars that this fish, like the cod, and 

 many of the flat fish, etc., spawns in the open sea, some times at a great distance from the land, at 

 others closer inshore. Sars found them on the outer banks of the coast of Norway; and Mr. 

 Matthias Dunn, of Mevagissey, England, communicates to ' Land and Water ' his observations 

 of Mackerel found, with ripe spawn, six miles from the coast. 1 



" The fish taken in the weirs and pounds on Vineyard Sound and about Cape Cod in the early 

 spring are filled with ripe spawn ; and that the operation of spawning takes place on the Ameri- 

 can coast is shown by the immense schools of small fish that are taken throughout the summer, of 

 various sizes, from a few inches up, and from Buzzard's Bay to Portland and Penobscot Bay. No 

 species of young fish is, at times, more abundant throughout the summer season than the Mackerel. 



'The egg of the Mackerel is exceedingly minute, not larger than that of the alewife or gaspe- 

 reau. It appears to be free from an adhesive envelope, such as pertains to the egg of the herring, 

 and in consequence of which it agglutinates together, and adheres to gravel, the rocks, or the sea- 

 weed at the bottom. As with the egg of the cod, that of the Mackerel is provided with an oil 

 globule, which makes it float nearly at the level of the surface." 



I am indebted to Mr. Frederick W. True for an enumeration of the eggs in two Mackerel takeu 

 at Wood's Holl, Massachusetts, in May, 1873; one of these contained 363,107, the other 393,887. 



SIR: I have been agaiu fortunate in taking a Mackerel alive in the act of spawning, on the night of May 10, abont 

 six miles from land. A better specimen could not possibly be bad, and the roe ran freely without assistance. I got 

 a bucket of sea- water, and allowed the fish to spawn in it ; for some time I had a difficulty in finding what became of 

 it, as the globules would not reflect the light of the candle like the pilchard spawn ; but by running the water into a 

 clean bottle, and holding it to the light, I found them floating on the surface, but not so buoyant as the pilchard roe. 

 In this state they continued for about half an hour, and then gradually sank to the bottom; but, unlike the pilchard 

 spawn, they retained their vitality there for more than twelve hours. With the daylight the globules could scarcely 

 be discerned by looking directly down into the water ; but on holding it towards the light in a bottle they could be seen, 

 with that healthy, bright silvery hue so peculiar to living ones, each marked with a dark spot in the center. Believ- 

 ing the pilclutrd spawn would have reached you, I did not send you any of these. As I sent that spawn by post, I 

 suppose the bottle must have been broken in the post-bag. MATTHIAS DUNN (Mevagissey, Cornwall, May 15, 1871), 

 Land and Water, May 20, 1871, p. 353. 



