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Mamaroneck

Goa, formerly a stood of the Maratha pirates. ron ore is found in the neighborhood. Pop. (1901) 19,626. Mamaroneck, vil., Westchester Co., Y., 20 m. N.N.E. of New York, on Ílong Island Sound and the Mamaroneck R., and on th. N.Y. N. H. and H. R. R. it is chiefly a residential place, but has manufactures of machinery and gutta percha. Pop. (1905) 5,090. Mamelukes, a term derived from an Arabic word meaning “slaves.” They were originally a body of Turkish slaves (some 12,000) whom Sultan Es-Sālih Eyyūb introduced in the 13th century. After his death, and in the absence of capable successors, the Mamelukes elected a sultan out of their own number; and from that date, (1251) till 1517 Egypt was ruled, and well ruled, by a succession of these military ave-kings, , who are, usually ouped in two lines—the Bahri 1250–1388) and the Burji (1388– 1517). The occupant of the throne was the strongest man for the time being, and his successor was the stronger, man who ousted him. The Bahri rulers were mostly men of Turkish blood, while the Burji rulers were principally Circassians. The rule of these kings, however tumultuous and uncertain, was enlightened, and Egypt —Cairo in particular—owes to them the most beautiful of its mosques. In 1517 the dominion of the Mamelukes was overthrown by the Ottoman Turks under Selim I., who, however, left them supreme in the provinces. In the 18th century they were again absolute masters of the

Count though nominally subiect to Turkish rule. The Mamei. made their last noteworthy

appearance when Napoleon, defeated them (1798) at the battle of the Pyramids. Mehemet. Ali, acting for the Porte, finally crushed them in two treacherous massacres (1805 and 1811). See Makrizi's Histoire des Sultanes Mamlouks (trans. by Quatremère, 1837–41). M a m i a ni della Rovere, TERENzio, Count (1799–1885) Italian poet, philosopher, an statesman, was born at Pesaro; took part in the revolutionary movements of 1831, and was banished. He lived at Paristill 1847, and returning to Italy was Minister of the Interior in 1848. He held the chair of philosophy and of history in the University of Turin from 1857–60. Subsequently he was several times minister under Cavour. In philosophy he was first an empiricist, and gradually became a Plato;

nist. One of his works appeared in English (Rights of Nations, trans. by R. Acton, 1860). In his

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youth he versified sacred legends in the Inni Sacri (1832), and dealt with nature and national themes in the Idilli (1836). , All his works are inspired with the noblest patriotism. Mestica edited his Prose e Poesie Scelte (1886). See monoraphs by Gaspari (1888), Bianchi 1896), and Casini (2d ed. 1896). Mammals, the highest class of vertebrates, characterized by their hair and the fact that the young, are, suckled. Sometimes the hair is but scantily developed, and in the Cetacea it is functionally replaced by the layer of blubber—or fat—beneath the skin; but in all cases it is present to some extent, if only durin foetal life. In connection wit the hair, there is developed a system of skin glands, some of which are invariably modified to form, the mammary glands in which is secreted the milk forming the necessary, and only possible, food for the newly born young. The two cavities of chest and abdomen are separated by a complete muscular partition, the diaphragm, which has much to do with the movements of respiration. The heart is four-chambered, and the single aortic arch curves to the left side, and not to the right as in birds; the lungs lie i.". the chest cavity, and are not bound down by membrane, as in birds; the surface of the brain is usually well convoluted, and the brain shows a number of anatomical peculiarities. Similarly, the skeleton of a mammal can be distinguished from that of any other vertebrate by a number of characters. For example, in the skull there are two facets, or condyles, for articulation with the backbone; the lower jaw consists of but one bone at each side; there are three little bones in the middle ear; the sutures, or lines of iunction of the bones of the skull, , usually remain distinct throughout life; and , in most cases teeth of characteristic comR. are present in both jaws. gain, in the neck there are, with rare exceptions, only seven vertebrae; a bone called the coracoid, very important in birds and reptiles, is, except in monotremes, absent from the shoulder girdle of mammals. Mammals are typically, terrestrial animals, furnished with four limbs." But a few have be: come fitted like birds for an aerial life—e.g. bats. Many have become aquatic, and here the whales mark the culminating point; similarly the mole shows the maximum adaptation to the fossorial life, and the monkey to the arboreal. In classifying mammals, stress is laid in the first instance on the methods of reproduction. Mammals are in the general case distinguished from lower vertebrates

Mammals

by the fact that they give birth to living young, in #. of laying, eggs; but three living mammals lay eggs like birds and rep- }. - p tiles. It is, therefore, necessary to separate these mammals from the rest, and form of them a separate sub-class, called Prototheria, or primitive mammals. Above this sub-class we come to the order of marsupials (e.g. kanÉ.” in which the young are rn alive, but in a very imper: fect state of development, and are Fo after birth in a pouch by the mother. These constitute the sub-class Metatheria, or later mammals. . Finally, all, other mammals give rise to fully deyeloped young, and are included in the sub-class Eutheria, or welldeveloped mammals. In the Prototheria the brain is usually smooth, and its details of anatomy are somewhat reptilian; the coracoid is as well developed as in a reptile; as in marsupials, there are epipubic bones on the abdominal wall; , the mammae, present in all other mammals, are here absent, and the milk is secreted merely on a bare patch of skin, from which it is sicked by the young. Associated with the egg-laying habit are certain peculiarities of the reproductive organs of the reptilian, and not of the characteristic mammalian type. (See further ORNITHoRHYNCHUS and ECHIDNA.) In the marsupials, as in monotremes, two epipubic bones are present; but these have not, as was o supposed, anything to do wit the pouch. The brain is smaller and simpler than that of the higher mammals, and the reproductive organs are, generally speaking, intermediate between ose of monotremes and those of the higher mammals.

A point on which great stress was formerly laid in distinguishing , between Metatheria and

Eutheria is that, whereas in the latter the allantois unites with the uterine wall to form the complex structure known as the placenta, by means of which the unborn young are nourished during the prolonged period of gestation, in the marsupial the allantois remains small, and was formerly believed never to form a placentā. It has, , however, been recentl shown that in certain marsupia a true though small , allantoic placenta does exist, and the general belief now is that the marsupials have been descended from ancestors which possessed a placenta like that of the Eutheria. The effect of this new information is to merge the Metatheria with the Eutheria in a single sub-class (Eutheria). The marsupials were once widely distributed over the 3. but are now confined to the ustralian area, save for a few Mammals

which are found in America. In the Eutheria the period of gestation is relatively .# the §§ are nourished before birth the placenta, and their dependence on the mother's milk is less prolonged and less absolute than that of the marsupials. The brain is well developed, the reroductive organs are highly diferentiated; there, are no epipubic bones; as in marsupials the coracoids are represented merely by a process of the shoulder-blade. The mammalia may be classified as in the following table:

Sub-class: 1. PROTOTHERLA.

Order Monotremata—example, ornithorhynchus.

Sub-class: 2. METATHERLA. Order: Marsupialia - kan

garoo. Sub-class: 3. EUTHERLA. Orders– Edentata-sloth. Sirenia-manatee. Ungulata-horse. Cetacea--whale. Rodentia—rabbit. Carnivora–tiger. Insectivora-mole. Chiroptera—bat. § Primates—monkey. The lines of demarcation between these orders, as they now exist, are largely obliterated when the history of the orders is followed geologically. As we pass backward, the members of all approach more and more to generalized types, in which distinctions are lost; but whether all mammals originated from a single or sevj more or less allied sources is not known. It is perhaps now the general opinion that the monotremes are off the main line of descent—that is, that their immediate ancestors did not give rise to the other mammals. he earliest known mammals are found in the Triassic

It was the difficulties connected with the distribution of mammals that first directed Darwin alon the line of thought which ende in the publication of the Origin ! Species (1859). Such facts as the presence of marsupials in S. America and in Australia, but nowhere else, the presence of the tapir in . S. America and in the region of the Malay, of lemurs in Africa and in India, but nowhere else, and many similar problems otherwise insoluble, become at once explicable if, the theo there laid down granted. Some, problems of , distribution still, however, remain obscure— e.g. the reason for the disappearance of the horse from S. America rior to the human period. (See urther under EMBRYOLOGY.) See Mammals Living and Extinct, b Flower and Lydekker (1891);

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Mammalia, by F. G. Beddard (Cambridge Natural History, vol. x. 1902); and The Standard Natural History (1883–5) and Ernest Ingersoll's Life of Mammals (1906) may be consulted for more popular accounts. For distribution, consult A Geographical History of Mammals, by R. oo:: (i.896); and see also article GEOGRAPHICAL DISTRIBUTION. For fossil forms, see vol. ii. of Nicholson and Lydekker's Manual of Palaeontology (1889), and Woodward's Vertebrate Palaeontology (1898). For N. American mammals see D. G. Elliott's Synopsis (1901) and Mammals of Middle America (1904); and general works by Audubon and Bachman, Richardson, Godman, Merriam, Coues, Allen, Stone and Cram Ingersoll, and the publications of the U. S. Biological Survey. Mammea, a genus of tropical trees belonging to the order

Mammoth Cave

in countless shades. They generally bear spines in neat rosettes. Mammillarias are not difficult to row under #. if plenty of É. and moderate heat be afforded. They require a soil comed of sandy loam, finely-broken ricks, and lime rubbish.

Mammoth (Elephas antiquus), an extinct fossil elephant, characteristic of the glacial and tglacial periods. It differs little in anatomical structure from ex.# members of the same genus, and, like them, was a large animal with a height of from nine to eleven feet. But it had a thick covering of dark-brown hair, and is known to have fed on the shoots of coniferous trees. Great numbers of mammoth skeletons have been unearthed in Europe, but chiefly in N. Siberia and on the Arctic coasts, where they have been preserved in the frozen soil, often so completely that the flesh is

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eaten by the natives, by their dogs, and by wild animals. The tusks of the mammoth are sometimes more than ten feet long; and they are found in such abundance buried on the coasts and islands north of Siberia as to furnish a regular supply of good fossil ivory to the market. In the south of Europe the mammoth was contemporaneous with , cave man and rude but spirited sketches o it have been found engraved on ivory. , The same or a closely related species occurred less abundantly in .N., America, and perhaps survived until the advent of man, Why these animals have wholly is goat; is an unsolved problem. See Beddard Mammalia (1902), and compare MASTODON. Mammoth Cave. The la

known cavern in the world, situated in Edmonson co., Ky., 99.m. by rail S. by w. of Louisville; discovered in 1809. The imme! oliate district is one abounding in large caves and the surface is characterized by thousands of sinkholes. Mr. H. C. Hovey

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VIEWS OF MAMMOTH CAVE, KENTUCKY. 1. On Echo River. 2. The Acute Angle. 3. Martha Washington statue. 4. The Bottomless Pit, 5. The Arm Chair. 6. The Bridal Weil.

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Man

are the great pits, and domes, which are caverns of unusual vertical extent. They are in reality the same, pits ‘...."; downward and domes upward from the main points of observation. Crevice Pit with Klett's Dome, which is a part of it, is 150 feet in total vertical measurement. The Bottomless Pit is 105, and Scylla is 135 feet deep. Cleveland Avenue is 2 miles long, and Silliman's is 1}, and in places 200 feet wide. Many parts of the cave are beautifully incrusted with gypsum and other deposits, while stalactites and stalagmites are abundant in some of the lower portions. . Where these crusts are covered with crystals, their sparkling is especially impressive, as in Star Chamber. he Dead Sea, Lake Lethe, the Styx, and Roaring and Echo rivers are the largest stretches of Water. The outer galleries of the cave are inhabited by millions of bats. There are 2 species of blind fish, crayfish, crickets with abnormally long antennae, and a few insects. All of these are believed to have descended from former normal surface types and to have become modified by their subterranean env'ronment. The temperature of the cave is never above 59° nor below 52°F. Mammoth Hot Springs, a remarkable group of springs occupying about a thousand acres in the northern part of the Yellowstone National Park. Their waters, some of which reach a temperature of 165° F., have deposited great quantities of carbonates from solution #. the aid of organic growths. ese trayestine deposits form immense basins and a succession of terraces with fantastic outlines and varying colors on a scale unrivalled anywhere in the world.

Mammoth Tree. See SEQUOIA. Mamoré, riv., Bolivia, , S.

America, generally considered as the head-stream of the Madeira. See AMAZONS and PERU.

Man is so a member of the order Primates, and is most nearly related to the anthropoid apes, (family Simiidae). The distinguishing features which justify the erection for him of a separate family–Hominidae—are chiefly the following. The braincase and brain are proportionately much larger than in any ant o while the facial Dortion of the skull is reduced in size, and is placed at a different angle to the brain-case, being below instead of in front of it. In the male sex in the European races the brain has an aver weight of 1,360 grammes, while in the anthropoids the average weight is stated to be only 360 grammes. In man the teeth

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