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e do any other found in the Silurian.
The next and last group of fishes is known as Teleosts, or bony fishes. To this group belong our typical fishes, such as black bass, sun fishes, suckers, cat fishes and the like. None of this group lived during the Silurian.
The rays, fish-like animals much like Sharks, but with the body and fins flattened or spread out in a broad flat disc, appeared in the Jurassic. The Chimeras, so abundant in the Devonian and which died out apparently at the close of the Devonian, also reappeared at the beginning of the Jurassic. These did not belong to the same families as did the more ancient Chimeras. The Chimeras no doubt flourished in the Carboniferous and Triassic, but migrated to some portion of the sea where now perhaps their remains lie buried in rocks below the bottom of the sea. Their survivors, which were able to modify their structure and habits to become suited to new conditions, returned in modified forms in the Jurassic, where in time their remains come to the surface as fossils.
At the end of the Cretaceous or beginning of the Tertiary we find all of our modern types of sharks and all of the important orders of teleosts. The sturgeons and ganoids decreased throughout the Tertiary or Quaternary until at present we have but few living species. The sturgeons are the more abundant. Of the large group of Ganoids so abundant during all these geological ages but few forms are living to-day. These are the Ceratodus, lung fish of Australia; the Polypterus of the Nile, the Protopterus of Western Africa, the Dogfish and the three Garpike of North America. These few species are but the remnants of a once large and extensive group of fishes.
In the study of fishes we notice that some are highly specialized so far as their structures are concerned; the teeth of some become especially fitted for a peculiar kind of food, and as a result quite unfit for any other kind. Some, to be protected from their enemies, develop a heavy armor, which only retards their activity. Other fishes are more generalized; that is, are of medium size, omnivorous habits, are not hampered in their movements by a too heavy coat of mail, etc. When any change of conditions came to modify their habits of living the specialized were always the first to disappear. Being particularly fitted for one mode of life made them all the more unfitted for any other, and so when conditions changed they perished. All of our modern fishes except the few ganoids are more or less specialized. The trout lives in cool running water and some varieties can live in no other, while some fishes have become accustomed to warm, stagnant water and cannot live with the trout. What is true in this respect of fishes is true of land animals as well. The large, ponderous, slow-moving reptiles of the Triassic, Jurassic and the Cretaceous, and the large mammals of the Tertiary and Quarternary could not exist except under the peculiar conditions of that time, and sooner or later had to give way to the smaller, more active and more resourceful animals of their class.
In tracing the history of fishes from their earliest existence to the present one is struck with the myriad forms he finds. It would seem that all possible effort was made by them to modify their structure to suit their environment; when this changed all their efforts came to naught, and they were destined to give way to the more favored kinds. Seth E. Meek.
THE DEEP.
There's beauty in the deep-- The wave is bluer than the sky; And, though the light shine bright on high, More softly do the sea-gems glow That sparkle in the depths below; The rainbow's tints are only made When on the waters they are laid, And sun and moon most sweetly shine Upon the ocean's level brine. There's beauty in the deep.
There's music in the deep-- It is not in the surf's rough roar, Nor in the whispering, shelly shore-- They are but earthly sounds, that tell How little of the sea-nymph's shell, That sends its loud, clear note abroad, Or winds its softness through the flood, Echoes through groves with coral gay, And dies, on spongy banks, away. There's music in the deep.
There's quiet in the deep-- Above let tides and tempests rave, And earth-born whirlwinds wake the wave; Above let care and fear contend, With sin and sorrow to the end. Here, far beneath the tainted foam, That frets above our peaceful home, We dream in joy, and wake in love, Nor know the rage that yells above. There's quiet in the deep. John G. C. Brainard.
THE AMERICAN REDSTART.
Contemporaneous with the blossoming out of the wild plum, the early Richmond cherry and a rich and diversified profusion of woodland flowers, perhaps better exemplified on this occasion by such interesting types as the little Claytonia, or spring-beauty, the rue-anemone and the trilliums, both T. erectum and grandiflorum, with perhaps a few belated blossoms of the hepatica, is the advent of this interesting little bird among us, which here in Northeastern Illinois usually plans its arrival somewhere near the closing days of the first week in May.
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