moles short animal south body forelimbs
MOLE (contracted form of mould-warp, i.e., mould-caster), a term restricted in England to the common mole (Talpa europwa), a small, soft-furred, burrowing mammal, with minute eyes, and broad fossorial fore feet, belonging to the order Insectirora and family Ta/pida., but generally applied elsewhere to any underground burrowing animal of the class Mammalia. Thus, in North America we find, representing the same family, the star-nosed moles (Condylura), and the shrew moles (Scalops and Seapanus); in South Africa, the golden moles of the far-removed family Chrysochloridx ; and in South-East Europe, Asia, and South Africa, the rhizophagous rodent moles of the order 1?odentia and families Spalacithe and Muridre (see 11AMMALIA, VOL xv. pp. 405, 419, figs. 64 and 96).
Talpa europea, the Common Mole, type of the genus Talpa,1 is about six inches in length, of which the tail measures somewhat more than an inch ; the body is long and cylindrical, and, owing to the very anterior position of the forelimbs, the head appears to rest between the 'shoulders ; the muzzle is long and obtusely pointed, terminated by the nostrils, which are close together in front ; the minute eye is almost hidden by the fur ; the ear is without a conch, opening on a level with the surrounding integument ; the forelimbs are rather short and very muscular, terminating in broad, naked, shovel-shaped feet, the palms normally directed outwards, each with five subequal digits armed with strong flattened claws ; the hind-feet, on the contrary, are long and narrow, and the toes are provided with slender claws. The body is densely covered with soft, erect, velvety fur, - the hairs uniform in length and thickness, except on the muzzle and short tail, the former having some straight vibrissm on its sides, whilst the latter is clothed with longer and coarser hairs. The fur is generally black, with a more or less greyish tinge, or brownish-black, but various paler shades up to pure white have been observed.
The food of the mole consists chiefly of the common earth-worm, in pursuit of which it forms its well-known underground excavations. Its habits, so difficult to observe, were many years ago most patiently studied and described by M. Henri le Court. Like many other mammals the mole has a lair or fortress to which it may retire for security. This is constructed with much ingenuity. It consists of a central nest formed under a hillock which is placed in some protected situation, as under a bank, or between the roots of trees. The nest, which is lined with dried grass or leaves, communicates with the main-run by four passages, one of which only joins it directly, leading downwards for a short distance and then ascending again ; the other three are directed upwards and communicate at regular intervals with a circular gallery constructed in the upper part of the hillock, which in turn communicates by five passages leading downwards and outwards with another much larger gallery placed lower down on a level with the central nest, from which passages proceed outwards in different directions, one only communicating directly with the main-run, while the others, curving round, soon join, or end in culs-de-sac. The main-run is somewhat wider than the animal's body, its walls are smooth, and formed of closely compressed earth, its depth varying according to the nature of the soil, but ordinarily from four to six inches. Along this tunnel the animal passes backwards and forwards several times daily, and here traps are laid by mole-catchers for its capture. From the main-run numerous passages are formed on each side, along which the animal hunts its prey, throwing out the soil in the form of molehills. The mole is the most voracious of mammals, and, if deprived of food, is said to succumb in from ten to twelve hours. Almost any kind of flesh is eagerly devoured by captive moles, which have been seen by various observers, as if maddened by hunger, to attack animals nearly as large as themselves, such as birds, lizards, frogs, and even snakes ; toads, however, they will not touch, and no form of vegetable food attracts their notice. If two moles be confined together without food, the weaker is invariably devoured by the stronger. They take readily to the water - in this respect, as well as in external form, resembling their i. 3, c. prin. 1, in. 3 x 2 (T. wogura).
i. 3, c. prm. 4, m. 4 x 2 (T. leucrura, leptura).
i. 3, c. prin. g, in. 3 x 2 (T. mosclutta).
Except in T. curoptua, the eyes are covered by a membrane. In T. micrura the short tail is concealed by the fur. T. europant extends from England to Japan. T. cacti is found south of the Alps, the remaining species are all Asiatic, and of them two only - T. inicrura and T. leucrura - occur south of the Himalayas. (See Dobson, Monograph of the Insectivora, Part ii., 1883.) representatives on the North American continent. Bruce, writing in 1793, remarks that he saw a mole paddling towards a small island in the Loch of Clunie, 180 yards from land, on which he noticed molehills.
The sexes come together about the second week in March, and the young - generally from four to six in number - which are brought forth in about six weeks, quickly attain their full size.
skeleton very striking departures from the typical mammalian forms are noticeable. The first sternal bone is so much produced anteriorly as to extend forward as far as a vertical line bet down from the second cervical vertebra, carrying with it the very short almost quadrate clavicles, which arc articulated with its anterior extremity and distally with the humeri, being also connected ligamentously with the scapula. The forelimbs are thus brought opposite the sides of the neck, and from this position a threefold advantage is derived : - in the first place, as this is the narrowest part of the body, they add but little to the general width, which, if increased, would lessen the power of movement in a confined space ; secondly, this position allows of a longer forelimb than would otherwise be possible, and so increases its lever power; and, thirdly, although the entire limb is relatively very short, its anterior position enables the animal, when burrowing, to thrust the claws so far forward as to be in a line with the end of the muzzle, the importance of which is evident' Posteriorly, we find the hind limbs similarly removed out of the way by approximation of the hip- joints to the centre line of the body. This is effected forelimb is due to the humerus, which, like the clavicle, is so much reduced in length as to present the appearance of a flattened X-shaped bone, with prominent ridges and deep depressions for the attachments and origins of the powerful muscles connected with it. Its proximal extremity presents two rounded prominences : the smaller, the true head of the bone, articulates as usual with the scapuhe ; the larger, which is really the external tuberosity rounded off, forms a separate synovial joint with the end of the clavicle. This double articulation gives to a naturally loose joint the rigidity necessary to support the great lateral pressure sustained by the forelimb in excavating. The forearm bones are normal, but those of the forefeet are much flattened and laterally-expanded. The great width of the forefoot is also partly due to the presence of a peculiar falciform bone, lying on the inner side of the palm and articulating by its proximal extremity with the wrist. Into the radial side and under surface of this bone is inserted a tendon derived from that of the palmaris longus muscle, which, acting upon it as an abductor, separates it from the side of the palm, and so increases the width of the latter, at the same time rendering the palmar integument tense.
The muscles acting on these remarkably modified limbs are all homologous with those of the cursorial insectivora, differing only in their relative development. The tendon of the biceps traverses a long osseous tunnel, formed by the great expansion of the margin of the bicipital groove for the insertion of the large pectoralis major muscle ; the anterior division of the latter muscle is unconnected with the sternum, extending across as a muscular band between the humeri, and co-ordinating the motions of the forelimbs. The teres major and latissimus dorsi muscles are of immense size, probably relatively larger than in any other mammal, and are inserted together into the prominent ridge below the pectoral attachment ; they are the principal agents in the excavating action of the limb. The cervical muscles connecting the slender scapuke, and through them the forelimbs, with the centre line of the neck and with the occiput are large, and the ligamentum uucInv between them is ossified (as in all true moles) ; the latter condition appears to be