But about this common thing, an Egg? It is the germ or seed, so to speak, of animal life; in it is contained all that is necessary for the formation of the perfect living creature; in that little oval case lie snugly packed up, bones, and muscles, and sinews, and all the delicate parts, organs, as they would be called, from a Greek word signifying an instrument, thus the tongue is an organ of speech, the eye of sight, and so on. But all these organs are in an _undeveloped_ state, as the flower is in the bud; develope is a French word, and signifies to unroll, or unfold. The animal is there in _embryo_; this again is Greek, and means a thing unperfected, or unfinished, so the poet Thompson says:-- "While the promised fruit Lies yet a little _embryo_ unperceived, Within its crimson folds." And so with closer reference to our subject, we might say, While the promised bird Lies yet a little _embryo_ unperceived, Within its oval shell. Dr. Harvey, who made that great discovery, the circulation of the blood, uttered a truth when he said _omne animal ex ovo_, every animal is born of an egg, for although some animals are _oviparous_, and others _viviparous_,--the two words come from _ovum_ egg, _vivum_ life, and _pario_ to bring forth--yet may the first stage of all animal life be compared to an Egg. From the smallest insect up to the most huge and unwieldy creature that swims in the deep sea, or walks upon the land. All were at one time alike, mere specks, surrounded by fluid matter, which afforded the material for growth and nourishment, and enclosed in some kind of a case, which if not exactly like an egg shell, answers the same purpose of protection from injury.