« ElőzőTovább »
the natural result of a more extended acquaintance with this subject. The feelings of disgust with which, doubtless, the sight of most reptiles now fills you, will give way to some degree of satisfaction at least, if not of pleasure, by reason of the interest which a knowledge of their structure, character, and habits will excite in you. If we could look upon all God's creatures with pleasure, and find something to interest us in all of them, even the humblest, how much would our stock of general happiness be increased thereby!
6. But let us return to our subject, and see if we can not treat of it in a more scientific order. As tortoises are included in the great division of vertebrated animals, you will naturally ask, "for what réason'?” I reply, “Because they have a back-bone or spinal column.” “But the tortoise,” you say, “is a soft animal, between two shells, and I see no such
bone in its body.” Let me explain to you. The back-bone of the tortoise is on the outside of the body, and forms a part of its shell, or covering. Here is a drawing which will make it all plain to you. It represents the under side of the upper shell of the tortoise, with the bones of the limbs attached in their proper places. Downward through the length of the shell runs the spinal column; branching out from each side of it are the flat ribs, which
have so grown together as to leave only a Upper shell of Tortoise. mere line-mark to show where they are united. Thus the spinal column and the ribs grow on the outside, so as to form the upper shell of the animal.
7. “This is wonderful,” you say; " what I had never thought of before.” Do you see any wisdom', or apparent design', in such an arrangement'? The tortoise, when on land, is a slow animal, and it has a soft body, which, if unprotected, would be easily crushed, or destroyed by other animals. The peculiar growth of its back-bone and ribs has given it a firm bony shell to protect it from above; and in a similar manner the breast-bone, or sternum (which has been removed in the drawing), spreads out, in a shell-like form, extending from the base of the neck to the tail. By this singular provision the turtle is incased in a coat of bony armor, formed from its own skeleton! It will be well for you to recollect that the upper shell is called the carapace, and the lower one the plastron.
8. The Chelonian order of reptiles (for it is well to know the terms which scientific men use)—the Chelonians, I say, may be conveniently divided into the three following families: land tortoises, river and marsh tortoises, and marine turtles; although Agassiz divides them into two classes, with seven families in one, and two in the other, placing the land tortoises and the river and marsh tortoises in one class, and the marine turtles in the other. I shall not have room in this letter to describe any of these classes or families, but in my next I will give you some account of a few of the most important or most noted species. 1 CHE-LO'-NI-AN, from the Greek chel-o-ne, a 5 AG-AS-stz (ig'-u-se, or a-gås'-siz). tortoise.
6 Fo'-LI-o, a book formed by once doubling 2 MB-TBŪP'-O-Lis, chief city (New York). each sheet of paper. 3 HÄB'-MO-NY, just adaptation of parts to ? Ex'-QUI-SITE, choice; exceedingly beautieach other.
[tory. ful. • NĂT'-U-BAL-IST, one versed in natural his-8 €ĂB-A-PACE'.
LESSON III.-A SECOND LETTER ABOUT TURTLES.
Scale of Inches. LAND, MARSH, AND RIVER TORTOISES.-1. Salt-water Terrapin, Emys palustris. 2. Blanding's Tortoise, Cistuda Blandingii. 3. Spotted Tortoise, Emys guttata. 4. Freshwater, or Wood Terrapin, Emys insculpta. 5. Alligator Tortoise, or Snapping Turtle, Emysaura serpentina. 6. Common Mud-Turtle, or Musk Tortoise, Sternotherus odoratals. 7. Matamata Tortoise, Chelys matamata. 8. Common Box-Tortoise, Cistuda Carolina. (Nos, 2 and 8 are Land Tortoises.)
Dellwild, May 24th, 18—. 1. MY YOUNG FRIEND,-I proceed now to fulfill the promise which I made in my last letter. . Among the land tor
toises, which vary from a few inches to three or four feet in length, the best known to us is the little box-tortoise, which is found every where in this country on dry land. (See No. 8.) It is a very gentle and timid animal, never takes to the water from choice, and feeds on insects and fruit. The little land tortoise of Europe is extensively used in Greece for food. One kept in the garden of Lambeth Palace, near London, lived to the age of one hundred and twenty years. Some of the largest land tortoises, often weighing two or three hundred pounds, are often found on the Galapagos Islands, where they are considered wholesome and palatable2 food. They are eagerly sought for by crews of vessels, as they serve for fresh meat, and can be kept for a year in the hold of a ship without food or drink. In some of the land tortoises, the lower shell, or plastron, is so jointed that the animal, after drawing in its limbs, can shut the doors of its portable house against its enemies.
2. Of the marsh and river tortoises there is a great variety, differing much in size and character. Of these, a great many species, some of which are commonly known as terrapins, and others as mud-turtles, are found in this country. The wellknown and justly prized terrapin of epicures,3 which is called the salt-water terrapin, because it is found exclusively in salt or brackish streams near the sea-shore, is quite abundant on the shores of Long Island. During the winter it buries itself in the mud, from which it is taken in great numbers in early spring, and is then very fat.
3. Among the river tortoises is the well-known alligator tortoise, or snapping turtle, which derives its name from its propensity to snap at every thing within its reach. It will snap greedily at the legs of ducks in a pond, and drag them under water to be devoured at leisure. In the Southern United States this and other river turtles destroy great numbers of young alligators. Another large river turtle, also frequently called “snapping turtle,” and found abundantly in the rivers which enter the Gulf of Mexico, we have represented in the engraving on the next page. But I must not omit to mention the matamata, found in South America. It is the most remarkable of the river tortoises. Look at the drawing of it! What a hideous looking object! Yet its flesh is much esteemed for food, and it is angled for with a hook and line. It is an ugly creature to deal with, as it bites sharply; and the fishermen generally cut off its head as soon as they have caught it.
4. And, lastly, I must describe to you, briefly, the marine tortoises, which are considered the only true turtles. You will at once distinguish them from all others by the paddlelike form of their feet, the toes being concealed by the skin, which completely envelops4 them. These animals, which are found in all the seas of warm climates, are excellent swimmers, but on land they shuffle along in a very awkward manner, and make only a slow progress. The best-known species is the green turtle, which is often seen in the markets of New York, and is well known to the epicure for its delicious steaks, and the savory soup which it affords. The eggs of this, and, indeed, of all sea-turtles, are also eaten, and considered a great delicacy. These turtles are generally taken by watching them when they visit the shore to deposit their eggs; they are then turned over on their backs, and in this helpless condition they remain until their captors, having secured in the same manner as many as they require, carry them off to their ships.
Scale of Inches, MARINE AND RIVER TURTLES.-1. Hawk's-bill Turtle, Chelonia imbricata. 2. Loggerhead Turtle, Chelonia caretta. 3. Green Turtle, Chelonia mydas. 5. Leathery Turtle, Spharqis coriacea. 4.& 6. Upper and under sides of the Chelonura Temninckii, a "Snapping Turtle" of the Mississippi.
receives its popular name from the curved and pointed form of the upper jaw, furnishes the valuable tortoise-shell of commerce. The upper shell of this species consists of thirteen plates, partly overlapping each other like the tiles of a house. By means of heat these plates are capable of being firmly united in any quantity, and of receiving any shape by being pressed between metallic moulds. Those which produce the finest shell are taken in the waters of the Indian Archipelago. But the largest of the sea-turtles is the loggerhead, which sometimes weighs eleven hundred pounds. It is found occasionally on the shores of nearly all the Atlantic States, is a strong swimmer, and is frequently seen in the midst of the ocean, floating on the surface of the waters, motionless, and apparently asleep, in which situation it is easily captured.
6. Thus I have given you a very brief description of the turtle family, which comprises the first division or order of the class of reptiles. From what I have written, and from the drawings which I have given you, do you see any thing decidedly disagreeable or offensive in these animals' ? On the contrary, is it not probable that you might, like an Agassiz, become much interested in studying the peculiarities of their structure, their character, and their habits?? I might give you statistics of their commercial importance, and many interesting accounts of their habits from the pages of Audubon, Darwin, and others, and I regret that I have not room for them here. One thing which I had overlooked I must however remind you of, and that is, you must not forget that all the turtles, even those that live in the sea, can breathe only when they are out of the water, and that, like whales, porpoises, and dolphins, they must occasionally come to the surface for a supply of air. Large numbers of sea-turtles may sometimes be seen in the clear waters of the Indian Seas feeding upon sea-weeds at the bottom, and in that situation they are represented as appearing like so many cattle browsing5 upon the herbage. Like herds of bison, they probably have their ranges—their paths over the hills, and through the valleys of the sea, from one pasture-ground to another. Who shall doubt that their life beneath the waters is a happy one? I GAL-A-PA'-G09, the “islands of tortoises,"|3 FP'-I-CŪRE, one who indulges in the luxu
ries of the table. 4 EN-VĚL'-OPS, covers; incloses. 15 BROWS'-ING, feeding on branches.
are west of South America. 2 PĂL'-A-TA-BLE, agreeable to the taste.