We have already, and more than once, employed the word _perianth_[58] to designate the calyx or corolla, whether taken separately or together. In the former case, the _perianth_ is _simple_; in the latter, it is _double_. A more appropriate word could not be made use of. It is derived from the Greek πεσὶ, around, and ἃνθος, flower; and literally signifies, "floral envelope." Simple or double, this envelope is the metamorphosis of several leaves, never of a solitary one, inserted upon planes so closely brought together that they seem confounded. Observe, in fact, how the leaves tend to efface their intervals on the blossom-bearing spray; they draw towards each other, they are apparently in eager haste to accomplish their destined transformation. What eloquence there is in this simple language of nature! * * * * * _The Calyx._--The outermost whorl, or verticle, of the flower is called the _calyx_. And why? Out of a notion altogether incorrect. It is true that this foliaceous envelope may often assume the shape of a cup (in Latin, _calix_), and hence that the name has about it a semi-poetical air. But this only occurs when the calyx is composed of a _single_ leaf, which has procured for it the special designations of _monosepalous_, _gamopetalous_, and _monophyllous_,--three different words expressing one and the same thing! The violet and the primrose are examples of a monophyllous, monosepalous, or gamopetalous calyx. I see, dear reader, that you are puzzled by the word _sepal_. Certainly you would look for it in vain in any classical dictionary; it is neither Greek nor Latin. It was only invented, scarce a century ago, by a Swiss botanist, whose works have chiefly remained in manuscript,--by Necker, brother of the celebrated minister of Louis XVI., and uncle of the illustrious Madame de Staël. Let me explain the circumstance which determined, I suspect, the choice of this fanciful word,--a word belonging to no language but that of modern botanists. The botanists of antiquity called the coloured leaflets of the corolla, _petals_. In this they were doubly right; for, first, they are, in reality, nothing but metamorphosed leaves; second, the word _petal_ (in Greek, πέταλον) signified "a leaf" as early as the days of Homer, who, when speaking of the nightingale, says, like a keen observer of nature, that this bird, on the return of spring, sings-- "Couched among the thick leaves of the grove." (Δενδρέων ἐν πετάλοισι καθεζομένη πυκινοῖσιν.)[59]