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Mamaroneck

Goa, formerly a stronghold of the Maratha pirates. Iron ore is found in the neighborhood. Pop. (1901) 19,626.

Mamaroneck, vil., Westchester co., N. Y., 20 m. N.N.E. of New York, on Long Island Sound and the Mamaroneck R., and on the 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-Sâlih Eyyub 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 slave-kings, who are usually grouped in two lines-the Bahri (1250-1388) and the Burji (13881517). 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 country, though nominally subject to Turkish rule. The Mamelukes 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).

He

Mamiani della Rovere, TERENZIO, COUNT (1799-1885), Italian poet, philosopher, and statesman, was born at Pesaro; took part in the revolutionary movements of 1831, and was banished. He lived at Paris till 1847, and returning to Italy was Minister of the Interior in 1848. 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 Platonist. 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 monographs 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 during fœtal life. In connection with 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 freely in 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 junction of the bones of the skull, usually remain distinct throughout life; and in most cases teeth of characteristic complexity are present in both jaws. Again, in the neck there are, with rare exceptions, only seven vertebræ; 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 become fitted like birds for an aërial 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 place of laying eggs; but three living mammals lay eggs like birds and reptiles. It is, therefore, necessary to separate these mammals from all 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. kangaroo) in which the young are Born alive, but in a very imperfect state of development, and are placed 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 developed 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 mammæ, present in all other mammals, are here absent, and the milk is secreted merely on a bare patch of skin, from which it is licked 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 formerly supposed, anything to do with the pouch. The brain is smaller and simpler than that of the higher mammals, and the reproductive organs are, generally speaking, intermediate between those 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 placenta. It has, however, been recently shown that in certain marsupials 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 globe, but are now confined to the Australian area, save for a few

Mammals

which are found in America. In the Eutheria the period of gestation is relatively fong, the young are nourished before birth by 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 reproductive organs are highly differentiated; 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. PROTOTHERIA.

Order Monotremata- - example, ornithorhynchus. Sub-class: 2. METATHERIA. Order: Marsupialia

garoo.

Sub-class: 3. EUTHERIA.
Orders-

Edentata-sloth.
(2) Sirenia-manatee.
(3) Ungulata-horse.
(4) Cetacea-whale.

Rodentia-rabbit.
(6) Carnivora-tiger.
Insectivora-mole.
Chiroptera-bat.
Primates-monkey.

kan

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 several 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. The earliest known mammals are found in the Triassic beds.

It was the difficulties connected with the distribution of mammals that first directed Darwin along the line of thought which ended in the publication of the Origin of 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 theory there laid down be granted. Some problems of distribution still, however, remain obscuree.g. the reason for the disappearance of the horse from S. America prior to the human period. (See further under EMBRYOLOGY.) See Mammals Living and Extinct, by Flower and Lydekker (1891);

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For

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. Lydekker (1896); and see also article GEOGRAPHICAL DISTRIBUTION. fossil forms, see vol. ii. of Nicholson and Lydekker's Manual of Paleontology (1889), and Woodward's Vertebrate Paleontology (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

Guttiferæ. They bear indehiscent drupes, the best-known species, M. americana (of the West Indies), the mammee apple or wild apricot, being especially valued for its fruit. This is of variable size, sometimes as large as an orange, and similar in shape. Its sweet, yellow pulp, of aromatic odor, is protected by a thin, bitter, inner rind and an outer one, which is thick and leathery. The aromatic liqueur eau de Créole is distilled from the flowers of this species which are white and fragrant. The wood is useful for cabinet work, is fine grained and durable when in contact with moisture.

Mammillaria, a genus of succulent plants belonging to the order Cactaceæ, divided into many genera and species. They bear usually solitary flowers growing from the axil of the tubercle. The plants average about six inches in height, the stems being cylindrical or globular, and the plants absolutely symmetrical in form. The blossoms are gay, white, yellow, red, and purple,

Mammoth Cave

in countless shades. They generally bear spines in neat rosettes. Mammillarias are not difficult to grow under glass if plenty of light and moderate heat be afforded. They require a soil composed of sandy loam, finely-broken bricks, and lime rubbish.

Mammoth (Elephas antiquus), an extinct fossil elephant, characteristic of the glacial and postglacial periods. It differs little in anatomical structure from existing 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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Skeleton.

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 of 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 disappeared is an unsolved problem. See Beddard Mammalia (1902), and compare MAS

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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 Veil.

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1. Skull of gorilla. 2. Skull of man. 3. Brain of gorilla. 4. Brain of man. 5. Skull of Pithecanthropus erectus, side and top view. 6. Neanderthal skull, side and top view. 7. Vertebral column of gorilla. 8. Vertebral column of man. 9. Vertebral column of child. 10. Foot of gorilla. 11. Foot of man. 12. Hand of gorilla. 13. Hand of man.

surface water immediately finding its way into the sinks and through the subterranean caverns and channels that everywhere abound. Green river, which gathers most of these waters, flows from 300 to 600 feet below the general level of the upland country and many of the caverns reach down to this underground water level. This action is now

process in other limestone regions. Mammoth Cave is in reality a complex series of more than 200 socalled rooms, chambers, domes, abysses, pits, grottoes, avenues, and galleries extending for 9 miles underground. In certain of the lower caverns there are rivers, cataracts, and lakes, varying in volume with local rain supply. The most remarkable portions

Man

are the great pits and domes, which are caverns of unusual vertical extent. They are in reality the same, pits extending 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 11, 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.

The Dead Sea, Lake Lethe, the Styx, and Roaring and Echo rivers are the largest stretches of

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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 antennæ, 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 environment.

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 by the aid of organic growths. These travestine 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 SE

QUOIA.

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

Man is zoologically a member of the order Primates, and is most nearly related to the anthropoid apes (family Simiida). The distinguishing features which justify the erection for him of a separate family-Hominida-are chiefly the following. The braincase and brain are proportionately much larger than in any anthropoid, while the facial portion 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 average 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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