796 



tractions. The ends of the muscles are 

 fastened to the bones which they move, 

 and when they act in opposition to each 

 other, they are called antagonists. An 

 almost infinite variety of arrangement is 

 found in the muscular fibres adapted to 

 the especial purpose which eacli muscle has 

 to fulfil, whether it be chiefly strength of 

 action, or rapidity or extent of motion ; 

 and all are guided by the nicest mechani- 

 cal rules. It is also constantly found that 

 where power is lost, a corresponding gain 

 of velocity or extent of motion, or of con- 

 venience and compactness of form, and 

 readiness of action, is obtained. 

 MUSCULAR IMPRESSIONS. The marks or in- 

 dentations in the shells of acephalous bi- 

 valves, which indicate the insertion of the 

 muscles, by which the animal is attached 

 to its shell. 



MUSEUM. A building appropriated as a re- 

 pository of things that have an immediate 

 relation to science and the arts. The 

 noble edifice in Russell Street, London, 

 most appropriately called the British Mu- 

 seum, is of first-rate magnitude, and, to 

 say nothing of its vast and unequalled 

 library, is replete with the wonders of 

 Nature and Art, collected from every part 

 of the globe, and arranged with consum- 

 mate skill. This magnificent collection 

 of all that is valuable and interesting is 

 alike worthy of the nation whose name it 

 bears, of those distinguished men who 

 have contributed to its treasures, and of 

 the savans to whose care and management 

 the whole is entrusted It is highly gra- 

 tifying to be able to add, that at the present 

 time a most laudable spirit exists, among 

 all classes in this country, to imitate the 

 example of the metropolis ; and we ac- 



cordingly hear of Museums, already esta- 

 shed or being in embryo, in almost every 



bli 



town in the United Kingdom 



MUSTELINE. Pertaining to the weasel, or ani- 

 mals of the genus Mustela. 



MUTILATE. When the base-covers of an 

 insect appear unnaturally short or curtailed 

 as if mutilated. 



MUZZLE. The mouth and parts immedi- 

 ately adjacent to it. 



MYELENCEPUALA. The primary division of 

 animals characterized by a brain and 

 spinal marrow. 



MYOGRAPHY. A description of the muscles. 



MYRIAD. An immense but indefinite num- 

 ber. 



MYRIAPOD. Having two hundred legs or 

 more ; an insect belonging to the order 

 Myriapoda, which are characterized by 

 their numerous feet. 



MYTILITE. A petrified shell of the genus 

 Hytilus. 



NACRE. Mother-of-pearl ; the white shining 

 substance which constitutes the interior 

 surface of a shell producing a pearl. 



NACRED. NACREOUS. Having a pearly 

 lustre ; like mother-of-pearl. 



NASCENT. Beginning to exist or to grow ; 

 coming into being. 



NATANT. Swimming, or floating on the 

 water. 



Bhi 



l:;\v 



NATATORIOUS. When the legs of insects are 

 compressed and ciliated, and formed for 

 swimming. Also, when the abdomen is 

 terminated by flat foliaceous appendages, 

 or the tail is ciliated on each side with 

 dense parallel hairs, which assist the insect 

 in swimming. 



NATATORY. Formed for swimming ; enabling 

 to swim. 



NATURE. This word is variously used in 

 works on Natural History. It sometimes 

 denotes the qualities which a being derives 

 from birth, in opposition to those which it 

 may owe to art ; at other times, the ag- 

 gregate of beings which compose the uni- 

 verse ; and sometimes, again, the laws 

 which govern these beings. In this latter 

 sense it has become customary to personify 

 Nature, and to employ the name for that 

 of its Great Author. 



NATURAL. Produced by or derived from 

 nature. 



NATURALIST. One that is versed in Natural 

 History. 



NATURAL PHILOSOPHY. That branch of 

 ilosophy which treats of nature and its 

 ws. 



NAUTILITE. A fossil Nautilus. 



NAVICULAR. W T hen two sides meet and form 

 an angle like the outer bottom of a boat ; 

 boat-shaped. 



NEBUL.E. Cloudy or dusky specks. 



NEBUJ.OSE. NEBULOUS. Resembling a small 

 cloud or collection of vapours. 



NECROMORFHA. Insects in which the pupa 

 has the mouth and organs of locomotion 

 detached from the body, but so enveloped 

 in a case or sheath, that it can employ 

 neither. This group contains the Hy- 

 menoptera and CoJeoptera. 



NECTAREOUS. Resembling nectar ; very 

 sweet and pleasant. 



NECTARY. The melliferous part of a flower : 

 sometimes it is in the form of a horn or 

 spur ; sometimes in that of a cup ; whence 

 it is called the honey-cup. 



NEIGH. To utter a sound, like the horse, 

 expressive of want or desire. 



NEGRO. A native or descendant of the black 

 race of men in the more southern parts of 

 Africa. 



NKMATOIDEA. The intestinal worms, which 

 are long and filiform. 



NEMATONEURA. A name applied to the 

 higher division of Cuvier's liadiata by 

 Professor Owen. 



NEOLOGIST. One who introduces or employs 

 new words in any science. 



NERVES. The nerves are the organs of 

 sensation : they originate in the brain, and 

 are prolongations of the medullary sub- 

 stance of the brain, which ramify and 

 extend over the whole body ; and they 

 consist of fine tubular filaments, which are 

 arranged nearly parallel to each other in 

 sheaths of fibrous tissue. " There are two 

 distinct systems of nerves ; one of which 

 is connected with the brain and the spinal 

 chord, and are media of sensation and of 

 voluntary motion. They are termed the 

 nerves of animal life, or the cerebro- spinal 

 nerves. The other system is only in com- 

 munication with the brain and spinal 



