GLOS 



Molt (M.E. mouten, from L. miitare, to 

 change). To shed an outer covermg. 



Mo-noe'cious. Containing both sexes in the 

 same organism, hermaphroditic. 



Mon'o-hy"brid (Gr. monos, single; L. hy- 

 brida, mongrel). The offspring of par- 

 ents differing in one character. 



Mor-phoro-gy (Gr. morphe, form; logos, 

 discourse). The study of form and 

 structure. 



Mu'cous (L. mucus, slime). Pertaining to 

 mucus. 



Mu'eus (L. mucus, slime). A watery secre- 

 tion which covers mucous membranes. 



Mu'tant (L. mutare, to change). A varia- 

 tion which breeds true. 



Mu-ta'tion (L. mutare, to change). A per- 

 manent transmissible change in the 

 character of an offspring. 



My'e-lin (Gr. mijelos, marrow). A fat-like 

 substance formins; a sheath around the 

 axis of a medullated nerve. 



My'o-fi"bril (Gr. mys, muscle; L. fibriUa, 

 a small fiber ) . One of the slender, pro- 

 toplasmic threads found in the muscle 

 fiber which runs parallel with the long 

 axis. 



Na'res (L. naris, nostril). Openings of the 

 air passages in vertebrates, both exter- 

 nal and internal. 



Na'sal (L. nasus, nose). Pertaining to the 

 nose. 



Nem'a-to-cyst (Gr. nema, thread; ki/stis, a 

 bladder ) . A stinging body found in co- 

 elenterates. 



Ne-phrid'i-o-pore (Gr. nephros, kidney; po- 

 ros, passage). The external opening of 

 the invertebrate excretory organ. 



Ne-phrid'i-um (Gr. nephros, kidney). An 

 invertebrate excretory organ. 



Neph'ro-stome ( Gr. nephros, kidney; stoma, 

 mouth). The funnel-shaped opening at 

 the inner end of the nephridium. 



Neu'ral (Gr. neuron, nerve). Pertaining to 

 the nervous system. 



Neu'ri-lem"ma (Gr. neuron, nerve; lemma. 



SARY 



695 



covering). The outermost nerve fiber 



sheath. 

 Neu'ron, or neu'rone (Gr. neuron, nerve). 



The nerve cell. 

 No'to-chord (Gr. notos, back; choreic, 



string). The cylindrical rod of suppor- 

 tive tissue found in chordates, dorsal to 



the digestive tract and ventral to the 



nerve cord. 

 Nu-cle'ol-us (L. diminutive of nucleus). A 



round, conspicuous body found within 



the nucleus of most cells. 

 Nu'cle-us (L. kernel). A dense spheroid 



body containing chromatin found 



within the cell. 

 Nu-tri'tion ( L. nutrimentum, nourishment). 



Sum total of the processes involved in 



food assimilation. 



Oc-cip'i-tal ( L. occiput, back of the head ) . 

 Pertaining to the back of the head. 



O-cel'lus (L. a little eye). The simple eye 

 found in invertebrates. 



Oc'u-lar (L. oculus, an eye). Pertaining to 

 the eye; also the eyepiece of a micro- 

 scope. 



Ol-fac'to-ry (L. olfacere, to smell). Pertain- 

 inor to the sense of smell. 



Om-ma-tid'i-um (Gr. omna, eye). A small 

 rod-like unit in the invertebrate com- 

 poimd eye. 



Om-niv'o-rous ( L. ominis, all; vorare, to de- 

 vour). Subsisting on food of all types. 



On-tog'e-ny (Gr. onto, being; genos, birth). 

 The evolution of developmental history 

 of an organism. 



O'o-cyte (Gr. oon, egg; kytos, cell). The 

 original cell of the ovarian egg before 

 the formation of polar bodies. 



0'o-gen"e-sis (Gr. oon, egg; genesis, ori- 

 gin). The origin and development of 

 the ovum. 



O'o-gon'i-um (Gr. oon, egg; gonos, off- 

 spring). The primordial cell which 

 gives rise to the ovarian egg. 



Oph-thal'mic (L. ophthalmia, the eye). 

 Pertaining to the eye. 



