202 LOWER VERTEBRATES. 



pointed head ; the spinous dorsal is low, and has fourteen to eighteen feeble spines ; 

 the second dorsal and anal are short and elevated, and each is succeeded by eight or 

 nine finlets ; the teeth in the jaws are strong and compressed, and fine teeth exist on 

 the vomer and palatines ; the color is bluish, tinged with silvery above, and along the 

 sides are numerous round bronze spots about as large as the pupil of the eye. 



Tn size the Spanish mackerel is smaller than most of its relatives, but the 

 average varies. According to Mr. Goode, as a rule, the first to arrive on our coast 

 are the largest, and measure from twenty to twenty-four inches, while those coining 

 later are only about twelve or fifteen inches long. Specimens of thirty-six and forty 

 inches are sometimes caught by the use of trolling-lines, but these fish are rarely found 

 in the schools. 



The Spanish mackerel is an inhabitant of the Caribbean seas and the coast waters 

 of America, considerably to the northward as well as southward. It is somewhat er- 

 ratic in its appearance, and has been much more abundant to the northward along our 

 coast of late years than formerly. It extends northward along the eastern coast as 

 far as Cape Cod ; on the western it is not found northward of Lower California. In 

 the 17th century it seems to have been moderately common, but for a long interval 

 no record has been preserved of its appearance. For some years, however, it has been 

 increasing in abundance, and is now a tolerably common fish, as well as the most 

 esteemed for the table. 



Along the Florida coasts, they are first seen in March or April, four or five miles 

 from land, moving along swiftly towards the eastward, or playing at the surface, with 

 no apparent aim or coxirse of movement. Along the North Carolina coast, they be- 

 come abundant in the latter part of August and September. On the Virginian, they 

 come in August and Sejitember, and stay until frost. According to Genio C. Scott, 

 writing in 1875, " every year the shoals of Spanish mackerel become more and more 

 numerous, and more are taken, but never in sufficient numbers to reduce the average 

 price below sixty cents per pound." The shoals which he saw, when last trolling for 

 them, would have formed " an area of nearly five miles square and still the most suc- 

 cessful did not take more than a dozen in three days. They will not bite at any arti- 

 ficial lures, and tliough numbers came near leaping on the top " of his yacht, they 

 treated the lures with an indifference that savored of perversity. 



Nothing was known concerning the reproduction of the Spanish mackerel until 

 1880. It was then found spawning abundantly in the Chesapeake bay, and the data 

 respecting its varying periods of deposition along the coast were also secured by Mr. 

 Earll. " The temperature of the water seems to have a decided effect upon the spawn- 

 ing time of the mackerel, and the ovaries and spermaries do not develop very rapidly 

 until it has risen to upwards of 72° Fahrenheit." In Carolina, spawning commences in 

 April, around Long Island in August, and in the intermediate Chesapeake region in 

 June. The season at any one locality lasts from six to ten weeks. The eggs, when 

 thrown from the parent, " rise to the surface, and are driven hither and thither by 

 the winds and tides during the earlier period of development." The time of hatch- 

 ing varies according to the temperature, but at 40° Fahrenheit almost all the eggs are 

 hatched, and the young feed within twenty hours and " fully half " eighteen hours after 

 fecundation. 



Passing over the numerous other species of the family, still other forms related, but 

 more distantly, deserve attention. 



Among the Scombridse we find fishes which exhibit different tendencies, finding 



