Morphology. The law of form or structure independent of function.
Nascent. Commencing development.
Nexus. Connection; tie.
Nictitating Membrane. A semi-transparent membrane, which can be drawn across the eye in birds and reptiles, either to moderate the effects of a strong light or to sweep particles of dust, etc., from the surface of the eye.
Noumenon (Metaph.). The of itself unknown and unknowable rational object, or thing in itself, which is distinguished from the phenomenon in which it occurs to apprehension, and by which it is interpreted and understood; so used in the philosophy of Kant and his followers.
Opossum. An animal of several species of marsupial quadrupeds of the genus Didelphys. The common species of the United States is the D. Virginiana. Another species, common in Texas and California, is D. Californica, and other species are found in South America.
Organism. An organized being, whether plant or animal.
Ovule. An egg. (Bot.) The rudimentary state of a seed. It consists essentially of a nucleus developed directly from the placenta.
Parasite. An animal or plant living upon or in, and at the expense of, another organism.