Page:Encyclopædia Britannica, Ninth Edition, v. 15.djvu/468

From Wikisource
Jump to navigation Jump to search
This page needs to be proofread.
ABC—XYZ

444 MAMMALIA [CARNIVORA. generally one-rooted. Nose of males with an appendage capable of being inflated. First and fifth toes of hind feet greatly exceeding the others in length, with prolonged cutaneous lobes, and rudi mentary or no nails. Cystophora. Dentition : i f , c, p f, m  ; total 30. The last molar has generally two distinct roots. Beneath the skin over the face of the male, and connected with the nostrils, is a sac capable of inflation, when it forms a kind of hood covering the upper part of the head. Nails present, though small on the hind feet. C. cristata, the Hooded or Bladder-Nose Seal of the Polar Seas. Macrorhinus. Dentition as the last, but molars of simpler char acter, and all one-rooted. All the teeth, except the canines, very small relatively to the size of the animal. Hind feet without nails. Vertebra : C 7, D 15, L 5, S 4, C 11. Nose of adult male pro duced into a short tubular proboscis, ordinarily flaccid, but capable of dilatation and elongation under excitement. One species, M. leonina, the Elephant Seal, or " Sea Elephant " of the whalers, the largest of the whole family, attaining the length of nearly 20 feet. Formerly abundant in the Antarctic Seas, and also found on the coast of California. EXTINCT PINNIPEDS. Remains of animals of this group have been found in late Miocene and Pliocene strata in Europe and America, the most abundant and best preserved being those of the Antwerp Crags, the subject of a recent illustrated monograph by Van Beneden. Nothing has, however, yet been discovered which throws any light upon the origin of the group, as all the extinct forms at present known come within the definition of the existing families ; and, though annectant forms between these occur, there are as yet no transitions to a more generalized type of mammal. Indeed, all those of which the characters are best known belong to the com pletely developed Phocine or Trichechine, not to the Otarine, type. The structure of the Pinnipeds is so clearly a modification of that of the terrestrial Carnivores, especially of the Arctoid type, that it is difficult to imagine that they can have had any other origin but one in common with that group ; but the separation must have taken place early in the Tertiary epoch, if not before. fiMiograpliy of Pinnipedia. J. A. Allen, History of North American Pinni peds, 1880 ; P. J. Van Beneden, Ossements fossiles d Anvers, pt. i., 1877. ORDER PRIMATES. This order in the system of Linnaeus includes Man, all the Monkeys, the Lemurs, and the Bats. By common con sent of all zoologists the last-named animals have been removed into a distinct order. With regard to the associa tion of the others, there has been, and still is, much difference of opinion. That all the Monkeys, from the highest Anthropoid Apes to the lowest Marmosets, form a natural and tolerably homogeneous group seems never to have been questioned ; but whether the Lemurs on the one hand and Man on the other should be united with them in the same order are points of controversy. With regard to the first, the question has already been referred to in the article LEMUR, in which an account has been given of the characters and the princi pal modifications of the type. If, in accordance with the traditional views of zoologists, they are still considered to be members of the order Primates, they, must form a sub order apart from all the others, with which they have really very little in common except the opposable hallux of the hind foot, a character also met with in the Opossums, and which is therefore of very secondary importance. The history of all the various forms of true Monkeys is very fully given in the article APE. The position of Man alone remains to be considered. In the Systema Natvrse, of Linnaeus he was separated only generically from the Apes, but in the next great work which exercised a wide spread influence over the progress of zoological science, the Regne Animal of Cuvier, he forms a distinct order under the name of Bimana, the Monkeys and Lemurs being associated together as Quadrumana. This has been the prevailing arrangement in the zoological systems of the present century, though in the classification of Owen his position is still farther removed from that of the Monkeys, as in it the genus Homo forms one of the four primary divisions or subclasses of the Mammalia, called Archence- phala, the Quadrumana being united with the Carnivora, Ungulata, and others in another division called Gyrence- phala. On the other hand the tendency of most modern systematists, for reasons which have been fully stated by Professor Huxley, 1 is to revert towards the Linneean position. Considering solely the facts of Man s bodily structure, it can be clearly demonstrated that the points in which he differs from the most nearly resembling Ape are not of greater importance than those by which that Ape differs from other universally acknowledged members of the group ; and therefore, in any natural system, if Man is to be made a subject of zoological classification upon the same principles as those applied elsewhere, he must be in cluded in the order which comprises the Monkeys. We say upon the same principles as are applied elsewhere, as zoological classification has never taken into consideration the psychological characteristics which distinguish the sub jects of its investigations, but only their tangible and physical structure, otherwise endless confusion would result, at all events with our very imperfect knowledge of animal psychology. The essential attributes which distin guish Man, and give him a perfectly isolated position among living creatures, are not to be found in his bodily structure, and therefore should either be left entirely out of consideration or have such weight given to them as would remove him completely out of the region of zoologi cal classification. To profess to classify Man as if he were one of the animals, as in all points of the structure and functions of his organs he undoubtedly is, to place him in the class Mammalia, and then to allow other con siderations to influence the judgment as to the particular position he should occupy in the class, is most illogical. Man, therefore, considered from a zoological point of view, must be included in the order Primates, even if the Lemurs are removed from it, as his structural affinities with the Monkeys are far closer than are those of the so- called " Half- Apes." We may, without treading upon debateable ground, go farther, and say that the differences between Man and the Anthropoid Apes are really not so marked as those which separate the latter from the American Monkeys. Perhaps the best exposition of the facts relating to the present condition of the order will be a division into five sections, which may be considered as families, of course without intending to imply that they are exactly equivalent, or that the intervals which separate them are of precisely the same importance, but that they are five distinct groups, all branches from a common stem, and unconnected in the present condition of nature by any intermediate forms. These are (1) Hominidx, con taining Man alone ; (2) /Simiidee, containing the four genera of Man-like Apes : Troglodytes, Gorilla, Simia, andllylobates ; (3) Cercopithecidse, containing all the remaining Old- World Monkeys ; (4) Cebidae, containing the American Monkeys having three true molar teeth on each side of each jaw ; and (5) Hapalidse., the American Monkeys with two molar teeth, or Marmosets. The distinctions between Hominidse and Simiidse, of which alone we have to treat at present, as the characters of the other families are given in the article APE, are chiefly relative, being greater size of brain and of brain case as compared with the facial portion of the skull, smaller development of the canine teeth of the males, more com plete adaptation of the structure of the vertebral column to the vertical position, greater length of the lower as com pared with the upper extremities, and greater length of hallux or great toe, with almost complete absence of the power of bringing it in opposition to the other four toes. The last 1 Man s Place in Nature, 1863, and Anatomy of Vertebrated Ani mals, 1871. See also the more recent investigations of Broca into the comparative structure of Man and the higher Apes, published mostly

in the Revue d Anthropologie.