Page:EB1911 - Volume 18.djvu/976

From Wikisource
Jump to navigation Jump to search
This page has been validated.
944
MOUSE BIRD—MOUTH
  

MOUSE-BIRD (Du. Muisvogel), the name by which in Cape Colony and Natal the members of the genus Colius of M. J. Brisson are known—probably from their singular habit of creeping along the boughs of trees with the whole tarsus applied to the branch. By the earlier systematists, Colius was placed among the Fringillidae; but the investigations of J. Murie and A. H. Garrod on its internal structure showed that it was not a true Passerine, and it is now placed in a separate family, Coliidae, amongst Coraciiform birds, near the trogons and swifts (q.v.). The Coliidae are small birds, with a rather finch-like bill, a more or less crested head, a very long tail, and generally of a dun or slate-coloured plumage that sometimes brightens into blue or is pleasingly diversified with white or chestnut. They feed almost wholly on fruits, but occasionally take insects, in quest of which they pass in bands of fifteen or twenty from tree to tree. Seven species are believed to exist, all belonging to the Ethiopian region (of which the Family is one of the most characteristic), and ranging from Abyssinia southwards. Three species inhabit Cape Colony.  (A. N.) 

Mouse-Bird.

MOUSSORGSKY, MODESTE PETROVICH (1835–1881), Russian composer, was born at Karevo, government of Pskov, in March 1835, and entered the army at an early age. He came of a musical family, and was himself a talented amateur, and an acquaintance with Balakirev and Dargomijsky led him to more serious study of composition, so that in 1857 he left the army and devoted himself to music, though this step entailed his earning his living as a government clerk and a prolonged period of poverty. His greatest opera, Boris Godounov, based on Pushkin's drama, was produced in St Petersburg in 1874, and on it his reputation stands as one of the finest creative composers in the ranks of the modern Russian school. He also wrote a number of songs and orchestral works, of a realistic national type. In later life he suffered much from ill-health, and died in St Petersburg on the 16th (28th) of March 1881.

MOUSTACHE, or Mustachio, the hair worn unshaven on the upper lip (see Beard). The spelling “moustache,” now the most common in English usage, is the French form of Ital. mustachio, an adaptation of a Doric dialectical μύσταξ, upper lip, also hair on the lip; this is generally taken to be a variant of μάσταξ, jaws, mouth, connected with μάσασθαι, to chew; cf. “mastic,” chewing-gum, and “masticate,” to chew.

MOUSTERIAN, the name given by the French anthropologist G. de Mortillet to the second epoch of the Quaternary Age, and to the earliest in his system of cave-chronology. It is so named from a cave (Le Moustier), on the right bank of the Vézère, an affluent of the Dordogne, above Les Eyzies and Tayac, which has yielded typical palaeolithic implements. The epoch was characterized by cold wet climate, by the supposed existence of Man of the Olom type, that is, nearly as dolichocephalous as the Neanderthal type, but with superciliary ridges flat, and frontal bones high, and by the occurrence of the musk-ox, the horse, the cave-bear, Rhinoceros tichorhinus and the mammoth. The typical implements are flint points or spear-heads, left smooth and flat on one side, as struck from the cave, pointed and edged from the other side; a scraper treated in the same way, but with edge rather upon the side than at the end, as in the succeeding Solutrian and Madelenian epochs. Relics of the Mousterian age have been also found in Belgium, southern Germany, Bohemia and southern England, some of the “finds” including human remains.

MOUTH AND SALIVARY GLANDS. The mouth (A.S. múð), in anatomy, is an oval cavity at the beginning of the alimentary canal in which the food is masticated. The opening is situated between the lips, and at rest its width reaches to the first premolar tooth on each side.

The lips (A.S. lippa) are fleshy folds, surrounding the opening of the mouth, and are formed, from without inward, by skin, superficial fascia, orbicularis oris muscle, submucous tissue, containing numerous labial glands about the size of a small pea, and mucous membrane. In the deeper part of each lip lies the coronary artery, while in the mid-line is a reflection of the mucous membrane on to the gum forming the fraenum labii.

The cheeks (A.S. céace) form the sides of the mouth and are continuous with the lips, with which their structure is almost identical save that the buccinator muscle replaces the orbicularis oris and the buccal glands the labial. In the subcutaneous fascia is a distinct mass of fat, specially large in the infant, which is known as the sucking pad. On the buccal surface of the cheek, opposite the second upper molar tooth, is the papilla which marks the opening of the parotid duct, while, just behind, are four or five molar glands, larger than the buccal, the ducts of which open opposite the last molar tooth. The mucous membrane of the cheek, like that of the rest of the mouth, is of the stratified squamous variety (see Epithelial Tissues) and is reflected on to the gums.

The gums (A.S. góma) consist of mucous membrane connected by thick fibrous tissue to the periosteum of the jaws. Round the base of the crown of each tooth the membrane rises up into a little collar.

The vestibule of the mouth is the space between the lips and cheeks superficially and the gums and teeth deeply. It communicates with the true cavity of the mouth by the clefts between the teeth and by the space behind the last molar teeth.

The roof of the mouth is concave transversely and antero-posteriorly, and is formed by the hard and soft palate. The hard palate consists of mucous membrane continuous with that of the gums and bound to the periosteum of the palatine processes of the maxillae and palate bones by firm fibrous tissue. In the mid-line is a slight ridge, the palatine raphe, which ends in front in a little eminence called the palatine papilla, marking the position of the anterior palatine canal. From the anterior part of the raphe five or six transverse ridges or rugae of the mucous membrane run outward. (For a description of the soft palate see Pharynx.)

The floor of the mouth can only be seen when the tongue is raised, then the reflection of the mucous membrane from the gums to it is exposed. In the mid-line is a prominent fold called the fraenum linguae, and on each side of this a sublingua papilla, on to the summit of which the duct of the submaxillary gland opens. Running outward and backward from this is a ridge called the plica sublingualis, which marks the upper edge of the sublingual gland, and on to which most of the ducts of that gland open. (For a description of the Tongue and the Teeth see special articles on those structures.)

The salivary glands are the parotid, submaxillary and sublingual, though the small scattered glands such as the labial, buccal, molar, lingual, &c., probably have a similar function.

The parotid gland (Gr. παρά beside, οὖς ear), is the largest of these glands, and is situated between the ear and the ramus of the mandible. In a transverse section through the head about the level of