346 Life and Health 



La-ryn'go-scope (Gr. \dpvy, larynx, and tr/coTretV, to behold). An instru- 

 ment consisting of a small mirror which may be held in the throat, and 

 a reflector to throw light on it, by which the interior of the larynx is 

 brought into view. 



Lens (Lat., a'lentil). A piece of transparent glass or other substance so 

 shaped as either to converge or disperse the rays of light. 



Lig'a-ture (Lat. ligarc, to bind). A thread of some material used in tying 

 arteries or other parts. 



Lymph (Lat. lympha, pure water). The watery fluid in the lymphatic vessels. 



MaHe-us (Lat. malleus, a hammer). The mallet; one of the small bones 

 of the middle ear. 



Me-a'tus (Lat. meare, to pass). A natural passage or canal. 



Me-dul'la ob-lon-ga'ta. The "oblong marrow," also called the spinal 

 bulb ; that portion of the brain which lies upon the basilar process of 

 the occipital bone. 



Mei-bo'mi-an. A term applied to the small glands between the conjunc- 

 tiva and tarsal cartilages, discovered by Meibomius. 



Mem-bra'na tym'pa-ni. Literally, " the drum membrane"; the membrane 

 separating the outer from the middle ear. 



Mes'en-ter-y (Gr. /^<ros, middle, and evrepov, the intestine). A fold of the 

 peritoneum, surrounding an intestine, especially the small intestine. 



Me-tab'o-lism. (Gr. /iera/SoXTj, change). The changes taking place in cells, 

 whereby they become more complex and contain more force, or less 

 complex and contain less force. The former is constructive metabolism, 

 or anabolism ; the latter, destructive metabolism, or katabolism. 



Mi'crobe (Gr. /xt/cp6s, little, and fos, life). A living organism of very small 

 size a micro-organism either animal or vegetable. 



More-cule (Lat. dim. of moles, a mass). The smallest portion of a sub- 

 stance which can retain the properties of the substance. 



Mor-phol'o-gy (Gr. /iop0^, form, and X67os, discourse). The science that 

 treats of form or structure of organized beings. 



Mo'tor (Lat. movere, to move). The name of the nerves which conduct 

 to the muscles the stimulus which causes them to contract. 



Mu'cous mem'brane. The thin layer of tissue which covers those internal 

 cavities or passages which communicate with the external air. 



Mu'cus. The thin glaify fluid secreted by mucous membranes. 



My-o'pia (Gr. friciv, to shut, and aty, the eye). A defect of vision dependent 

 upon too great length of the eyeball, rendering distant objects indistinct ; 

 nearsightedness. 



My'o-sin (Gr. /xus, muscle). Chief proteid substance of muscle. 



