THE SHAD'S ANNUAL PILGRIMAGE. 827 



abide in the shallows. Inasmuch, however, as the young shad 

 possess the continuous dorsal fin along the body incident to the 

 earliest and lowest fishes, the so-called instinct is most likely a 

 reversion to the ancestral habit, such forms being characteristic 

 of deep waters. 



Their burden laid down, their object accomplished, the parent 

 fish, worn with privation and spent with effort, turn at last sea- 

 ward. Emaciated and exhausted, they have become worthless to 

 the fisherman, who frequently observes them dead or apparently 

 dying, drifting down the stream. It is likely, however, that they 

 recuperate rapidly upon reaching the sea, having then access to 

 their customary food, and, if escaping marine carnivora and sur- 

 viving until the following spring, they renew their arduous voy- 

 age, stronger and larger fish, once more to strenuously strive and 

 suffer, but not probably again to return. For the mass of our 

 migratory fish may be likened to some of our familiar wayside 

 plants, that devote their vital energies to the fructification of their 

 seed : with its ripening they wither, with its complete formation 

 they die. 



Of the voided eggs, but a very small fraction develop, many 

 are unfertilized, many are devoured by various depredators, many 

 perish by changes in temperature, by floods, or by disturbances of 

 the place of deposit. Of the scanty remnant that become fry, 

 there again results a trifling fraction that mature ; many fall vic- 

 tims to innumerable enemies, to lack of sustenance, and to other 

 fatalities. Surviving all these, the young shad in a few months 

 descends the river ; then, quitting the fresh water that has nur- 

 tured and sustained it, launches boldly out for its distant and un- 

 known home in the obscurity of the great salt sea. Still in its new 

 and strange element does it run the gantlet of danger and death, 

 but instinct guides it to its ancestral abode, whence two or three 

 years later it emerges one of a host of adult fish burdened with a 

 sense of unaccomplished parentage. 



Leaving their home in the far deep, the shad, in beginning 

 their annual pilgrimage, rise to the surface and then direct their 

 course landward, the earliest migrants being those in which the 

 propagative function is most advanced. Pursuing their way over 

 the comparative shallows that widely fringe our continent, and 

 joined by other communities bent upon the same devoted errand, 

 they gather in our estuaries and about the mouths of our rivers, 

 and there they linger until the effluent waters are warmer than 

 those of the sea. With the manifestation of this sign the waiting 

 multitude, freighted with a dawning generation that engages 

 their overmastering solicitude, form into rank and column, and 

 with a common impulse set out to conclude their mission of self- 

 immolation and sacrifice for the maintenance of their race. 



