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Rambles of a Naturalist
No. II
On the day following my first related excursion, I started early in the morning, and was rewarded by one sight, which could not otherwise have been obtained, well worth the sacrifice of an hour or two of sleep. There may be persons who will smile contemptuously at the idea of a man's being delighted with such trifles; nevertheless, we are not inclined to envy such as disesteem the pure gratification afforded by these simple and easily accessible pleasures. As I crossed an open lot on my way to the lane, a succession of gossamer spider-webs, lightly suspended from various weeds and small shrubs, attracted my attention. The dew which had formed during the night was condensed upon this delicate lace, in globules of most resplendent brilliance, whose clear lustre pleased while it dazzled the sight. In comparison with the immaculate purity of these dew-drops, which reflected and refracted the morning light in beautiful rays, as the gossamer webs trembled in the breeze, how poor would appear the most invaluable diamonds that were ever obtained from Golconda or Brazil! How rich would any monarch be that could boast the possession of one such, as here glittered in thousands on every herb and spray! They are exhaled in an hour or two, and lost; yet they are almost daily offered to the delighted contemplation of the real lover of nature, who is ever happy to witness the beneficence of the great Creator, not less displayed in trivial circumstances, than in the most wonderful of His works.
No particular change was discoverable in the works of my little miners, except that all the places which had been a second time broken down, were again repaired, showing that the animal had passed between the times of my visit; and it may not be uninteresting to observe how the repair was effected. It appeared, when the animal arrived at the spot broken open or exposed to the air, that it changed its direction sufficiently downwards to raise enough of earth from the lower surface to fill up the opening; this of course slightly altered the direction of the gallery at this point, and though the earth thrown up was quite pulverulent, it was so nicely arched as to retain its place, and soon became consolidated. Having broken open a gallery where the turf was very close, and the soil tenacious, I was pleased to find the direction of the chamber somewhat changed: on digging farther with my clasp-knife, I found a very beautiful cell excavated in very tough clay, deeper than the common level of the gallery, and towards one side. This little lodging-room would probably have held a small melon, and was nicely arched all round. It was perfectly clear, and quite smooth, as if much used: to examine it fully, I was obliged to open it completely. (The next day, it was replaced by another, made a little farther to one side, exactly of the same kind: it was replaced a second time, but when broken up a third time, it was left in ruins.) As twelve o'clock approached, my solicitude to discover the little miner increased to a considerable degree: previous observation led me to believe that about that time his presence was to be expected. I had trodden down the gallery for some inches in a convenient place, and stood close by, in vigilant expectation. My wishes were speedily gratified: in a short time the flattened gallery began at one end to be raised to its former convexity, and the animal rapidly advanced. With a beating heart, I thrust the knife-blade down by the side of the rising earth, and quickly turned it over to one side, throwing my prize fairly into the sunshine. For an instant, he seemed motionless from surprise, when I caught and imprisoned him in my hat. It would be vain for me to attempt a description of my pleasure in having thus succeeded, small as was my conquest. I was delighted with the beauty of my captive's fur; with the admirable adaptation of his diggers, or broad rose-tinted hands; the wonderful strength of his fore-limbs, and the peculiar suitableness of his head and neck to the kind of life the Author of nature had designed him for. It was the shrew-mole, or scalops canadensis, whose history and peculiarities of structure are minutely related in the first volume of Godman's American Natural History. All my researches never enabled me to discover a nest, female, or young one of this species. All I ever caught were males, though this most probably was a mere accident. The breeding of the scalops is nearly all that is wanting to render our knowledge of it complete.
This little animal has eyes, though they are not discoverable during its living condition, nor are they of any use to it above ground. In running round a room (until it had perfectly learned where all the obstacles stood), it would uniformly strike hard against them with its snout, and then turn. It appeared to me as singular, that a creature which fed upon living earth-worms with all the greediness of a pig, would not destroy the larvæ or maggots of the flesh-fly. A shrew-mole lived for many weeks in my study, and made use of a gun-case, into which he squeezed himself, as a burrow. Frequently he would carry the meat he was fed with into his retreat; and, as it was warm weather, the flies deposited their eggs in the same place. An offensive odour led me to discover this circumstance, and I found a number of large larvæ, over which the shrew-mole passed without paying them any attention; nor would he, when hungry, accept of such food, though nothing could exceed the eager haste with which he seized and munched earth-worms. Often, when engaged in observing him thus employed, have I thought of the stories told me, when a boy, of the manner in which snakes were destroyed by swine: his voracity readily exciting a recollection of one of these animals, and the poor worms writhing and twining about his jaws answering for the snakes. It would be tedious were I to relate all my rambles undertaken with a view to gain a proper acquaintance with this creature, at all hours of the day, and late in the evening, before day-light, etc. etc.
Among other objects which served as an unfailing source of amusement, when resting from the fatigue of my walks, was the little inhabitant of the brook which is spoken of in the extract made from the "Journal of a Naturalist," in last week's Friend. These merry swimmers occupied every little sunny pool in the stream, apparently altogether engaged in sport. A circumstance (not adverted to in that extract) connected with these insects, gives them additional interest to a close observer – they are allied by their structure and nature to those nauseous vermin, the cimices, or bed-bugs; all of which, whether found infesting fruits or our dormitories, are distinguished by their disgusting odour. But their distant relatives, called by the boys the water-witches and apple-smellers, the gyrinus natator above alluded to, has a delightful smell, exactly similar to that of the richest, mellowest apple. This peculiarly pleasant smell frequently causes the idler many unavailing efforts to secure some of these creatures, whose activity in water renders their pursuit very difficult, though by no means so much so as that of some of the long-legged water-spiders, which walk the waters dry-shod, and evade the grasp with surprising ease and celerity. What purposes either of these races serve in the great economy of nature, has not yet been ascertained, and will scarcely be determined until our store of facts is far more extensive than at present. Other and still more remarkable inhabitants of the brook, at the same time, came within my notice, and afforded much gratification in the observation of their habits. The description of these we are obliged to defer for the present, as we have already occupied as much space as can be allowed to our humble sketches.
John.No. III
In moving along the borders of the stream, we may observe, where the sand or mud is fine and settled, a sort of mark or cutting, as if an edged instrument had been drawn along, so as to leave behind it a track or groove. At one end of this line, by digging a little into the mud with the hand, you will generally discover a shell of considerable size, which is tenanted by a molluscous animal of singular construction. On some occasions, when the mud is washed off from the shell, you will be delighted to observe the beautifully regular dark lines with which its greenish smooth surface is marked. Other species are found in the same situations, which, externally, are rough and inelegant, but within are ornamented to a most admirable degree, presenting a smooth surface of the richest pink, crimson, or purple, to which we have nothing of equal elegance to compare it. If the mere shells of these creatures be thus splendid, what shall we say of their internal structure, which, when examined by the microscope, offers a succession of wonders? The beautiful apparatus for respiration, formed of a network regularly arranged, of the most exquisitely delicate texture; the foot, or organ by which the shell is moved forward through the mud or water, composed of an expanded spongy extremity, capable of assuming various figures to suit particular purposes, and governed by several strong muscles, that move it in different directions; the ovaries, filled with myriads, not of eggs, but of perfect shells, or complete little animals, which, though not larger than the point of a fine needle, yet, when examined by the microscope, exhibit all the peculiarities of conformation that belong to the parent; the mouth, embraced by the nervous ganglion, which may be considered as the animal's brain; the stomach, surrounded by the various processes of the liver, and the strongly acting but transparent heart, all excite admiration and gratify our curiosity. The puzzling question often presents itself to the inquirer: Why so much elaborateness of construction and such exquisite ornament as are common to most of these creatures, should be bestowed? Destined to pass their lives in and under the mud, possessed of no sense that we are acquainted with, except that of touch, what purpose can ornament serve in them? However much of vanity there may be in asking the question, there is no answer to be offered. We cannot suppose that the individuals have any power of admiring each other, and we know that the foot is the only part they protrude from their shell, and that the inside of the shell is covered by the membrane called the mantle. Similar remarks may be made relative to conchology at large: the most exquisitely beautiful forms, colours, and ornaments are lavished upon genera and species which exist only at immense depths in the ocean, or buried in the mud; nor can any one form a satisfactory idea of the object the great Author of nature had in view, in thus profusely beautifying creatures occupying so low a place in the scale of creation.
European naturalists have hitherto fallen into the strangest absurdities concerning the motion of the bivalved shells, which five minutes' observation of nature would have served them to correct. Thus, they describe the upper part of the shell as the lower, and the hind part as the front, and speak of them as moving along on their rounded convex surface, like a boat on its keel, instead of advancing with the edges or open part of the shell towards the earth. All these mistakes have been corrected, and the true mode of progression indicated from actual observation, by our fellow-citizen, Isaac Lea, whose recently published communications to the American Philosophical Society reflect the highest credit upon their author, who is a naturalist in the best sense of the term.
As I wandered slowly along the borders of the run, towards a little wood, my attention was caught by a considerable collection of shells lying near an old stump. Many of these appeared to have been recently emptied of their contents, and others seemed to have long remained exposed to the weather. On most of them, at the thinnest part of the edge, a peculiar kind of fracture was obvious, and this seemed to be the work of an animal. A closer examination of the locality showed the footsteps of a quadruped, which I readily believed to be the muskrat, more especially as, upon examining the adjacent banks, numerous traces of burrows were discoverable. It is not a little singular that this animal, unlike all others of the larger gnawers, as the beaver, etc. appears to increase instead of diminishing with the increase of population. Whether it is that the dams and other works thrown up by men afford more favourable situations for their multiplication, or their favourite food is found in greater abundance, they certainly are quite as numerous now, if not more so, than when the country was first discovered, and are to be found at this time almost within the limits of the city. By the construction of their teeth, as well as all the parts of the body, they are closely allied to the rat kind; though in size, and some peculiarities of habit, they more closely approximate the beaver. They resemble the rat, especially, in not being exclusively herbivorous, as is shown by their feeding on the uniones or muscles above mentioned. To obtain this food requires no small exertion of their strength; and they accomplish it by introducing the claws of their fore-paws between the two edges of the shell, and tearing it open by main force. Whoever has tried to force open one of these shells, containing a living animal, may form an idea of the effort made by the muskrat: the strength of a strong man would be requisite to produce the same result in the same way.
The burrows of muskrats are very extensive, and consequently injurious to dykes and dams, meadow banks, etc. The entrance is always under water, and thence sloping upwards above the level of the water, so that the muskrat has to dive in going in and out. These creatures are excellent divers and swimmers, and, being nocturnal, are rarely seen unless by those who watch for them at night. Sometimes we alarm one near the mouth of the den, and he darts away across the water, near the bottom, marking his course by a turbid streak in the stream: occasionally we are made aware of the passage of one to some distance down the current, in the same way; but in both cases the action is so rapidly performed, that we should scarcely imagine what was the cause, if not previously informed. Except by burrowing into and spoiling the banks, they are not productive of much evil, their food consisting principally of the roots of aquatic plants, in addition to the shell-fish. The musky odour which gives rise to their common name is caused by glandular organs placed near the tail, filled with a viscid and powerfully musky fluid, whose uses we know but little of, though it is thought to be intended as a guide by which these creatures may discover each other. This inference is strengthened by finding some such contrivance in different races of animals, in various modifications. A great number carry it in pouches similar to those just mentioned. Some, as the musk animal, have the pouch under the belly; the shrew has the glands on the side; the camel on the back of the neck; the crocodile under the throat, etc. At least no other use has ever been assigned for this apparatus, and in all creatures possessing it the arrangement seems to be adapted peculiarly to the habits of the animals. The crocodile, for instance, generally approaches the shore in such a manner as to apply the neck and throat to the soil, while the hinder part of the body is under water. The glands under the throat leave the traces of his presence, therefore, with ease, as they come into contact with the shore. The glandular apparatus on the back of the neck of the male camel, seems to have reference to the general elevation of the olfactory organs of the female; and the dorsal gland of the peccary, no doubt, has some similar relation to the peculiarities of the race.
The value of the fur of the muskrat causes many of them to be destroyed, which is easily enough effected by means of a trap. This is a simple box, formed of rough boards nailed together, about three feet long, having an iron door, made of pointed bars, opening inwards, at both ends of the box. This trap is placed with the end opposite to the entrance of a burrow observed during the day-time. In the night, when the muskrat sallies forth, he enters the box, instead of passing into the open air, and is drowned, as the box is quite filled with water. If the traps be visited and emptied during the night, two may be caught in each trap, as muskrats from other burrows may come to visit those where the traps are placed, and thus one be taken going in as well as one coming out. These animals are frequently very fat, and their flesh has a very wholesome appearance, and would probably prove good food. The musky odour, however, prejudices strongly against its use; and it is probable that the flesh is rank, as the muscles it feeds on are nauseous and bitter, and the roots which supply the rest of its food are generally unpleasant and acrid. Still, we should not hesitate to partake of its flesh, in case of necessity, especially if of a young animal, from which the musk-bag had been removed immediately after it was killed.
In this vicinity the muskrat does not build himself a house for the winter, as our fields and dykes are too often visited. But in other parts of the country, where extensive marshes exist, and muskrats are abundant, they build very snug and substantial houses, quite as serviceable and ingenious as those of the beaver. They do not dam the water as the beaver, nor cut branches of trees to serve for the walls of their dwellings. They make it of mud and rushes, raising a cone two or three feet high, having the entrance on the south side, under water. About the year 1804, I saw several of them in Worrell's marsh, near Chestertown, Maryland, which were pointed out to me by an old black man who made his living principally by trapping these animals for the sake of their skins. A few years since I visited the marshes near the mouth of Magerthy river, in Maryland, where I was informed, by a resident, that the muskrats still built regularly every winter. Perhaps these quadrupeds are as numerous in the vicinity of Philadelphia as elsewhere, as I have never examined a stream of fresh water, dyked meadow, or mill-dam, hereabout, without seeing traces of vast numbers. Along all the water-courses and meadows in Jersey, opposite Philadelphia, and in the meadows of the Neck, below the Navy-Yard, there must be large numbers of muskrats. Considering the value of the fur, and the ease and trifling expense at which they might be caught, we have often felt surprised that more of them are not taken, especially as we have so many poor men complaining of wanting something to do. By thinning the number of muskrats, a positive benefit would be conferred on the farmers and furriers, to say nothing of the profits to the individual.
John.No. IV
My next visit to my old hunting-ground, the lane and brook, happened on a day in the first hay-harvest, when the verdant sward of the meadows was rapidly sinking before the keen-edged scythes swung by vigorous mowers. This unexpected circumstance afforded me considerable pleasure, for it promised me a freer scope to my wanderings, and might also enable me to ascertain various particulars concerning which my curiosity had long been awakened. Nor was this promise unattended by fruition of my wishes. The reader may recollect that, in my first walk, a neat burrow in the grass, above ground, was observed, without my knowing its author. The advance of the mowers explained this satisfactorily, for in cutting the long grass, they exposed several nests of field-mice, which, by means of these grass-covered alleys, passed to the stream in search of food or drink, unseen by their enemies, the hawks and owls. The numbers of these little creatures were truly surprising: their fecundity is so great, and their food so abundant, that, were they not preyed upon by many other animals, and destroyed in great numbers by man, they would become exceedingly troublesome. There are various species of them, all bearing a very considerable resemblance to each other, and having, to an incidental observer, much of the appearance of the domestic mouse. Slight attention, however, is requisite to perceive very striking differences, and the discrimination of these will prove a source of considerable gratification to the inquirer. The nests are very nicely made, and look much like a bird's nest, being lined with soft materials, and usually placed in some snug little hollow, or at the root of a strong tuft of grass. Upon the grass roots and seeds these nibblers principally feed; and, where very abundant, the effects of their hunger may be seen in the brown and withered aspect of the grass they have injured at the root. But, under ordinary circumstances, the hawks, owls, domestic cat, weasels, crows, etc. keep them in such limits, as prevent them from doing essential damage.
I had just observed another and a smaller grassy covered way, where the mowers had passed along, when my attention was called towards a wagon at a short distance, which was receiving its load. Shouts and laughter, accompanied by a general running and scrambling of the people, indicated that some rare sport was going forward. When I approached, I found that the object of chase was a jumping mouse, whose actions it was truly delightful to witness. When not closely pressed by its pursuers, it ran with some rapidity, in the usual manner, as if seeking concealment. But in a moment it would vault into the air, and skim along for ten or twelve feet, looking more like a bird than a little quadruped. After continuing this for some time, and nearly exhausting its pursuers with running and falling over each other, the frightened creature was accidentally struck down by one of the workmen, during one of its beautiful leaps, and killed. As the hunters saw nothing worthy of attention in the dead body of the animal, they very willingly resigned it to me; and with great satisfaction I retreated to a willow shade, to read what nature had written in its form for my instruction. The general appearance was mouse-like; but the length and slenderness of the body, the shortness of its fore-limbs, and the disproportionate length of its hind-limbs, together with the peculiarity of its tail, all indicated its adaptation to the peculiar kind of action I had just witnessed. A sight of this little creature vaulting or bounding through the air, strongly reminded me of what I had read of the great kangaroo of New Holland; and I could not help regarding our little jumper as in some respects a sort of miniature resemblance of that curious animal. It was not evident, however, that the jumping mouse derived the aid from its tail, which so powerfully assists the kangaroo. Though long, and sufficiently stout in proportion, it had none of the robust muscularity which, in the New Holland animal, impels the lower part of the body immediately upward. In this mouse, the leap is principally, if not entirely, effected by a sudden and violent extension of the long hind-limbs, the muscles of which are strong, and admirably suited to their object. We have heard that these little animals feed on the roots, etc. of the green herbage, and that they are every season to be found in the meadows. It may perhaps puzzle some to imagine how they subsist through the severities of winter, when vegetation is at rest, and the earth generally frozen. Here we find another occasion to admire the all-perfect designs of the awful Author of nature, who has endowed a great number of animals with the faculty of retiring into the earth, and passing whole months in a state of repose so complete, as to allow all the functions of the body to be suspended, until the returning warmth of the spring calls them forth to renewed activity and enjoyment. The jumping mouse, when the chill weather begins to draw nigh, digs down about six or eight inches into the soil, and there forms a little globular cell, as much larger than his own body as will allow a sufficient covering of fine grass to be introduced. This being obtained, he contrives to coil up his body and limbs in the centre of the soft dry grass, so as to form a complete ball; and so compact is this, that, when taken out with the torpid animal, it may be rolled across a floor without injury. In this snug cell, which is soon filled up and closed externally, the jumping mouse securely abides through all the frosts and storms of winter, needing neither food nor fuel, being utterly quiescent, and apparently dead, though susceptible at any time of reanimation, by being very gradually stimulated by light and heat.