A number of thoughts which occurred to us while writing the earlier pages of this work, related to our theme, yet not directly forming a part of it, seem to us of such interest and practical bearing, that it is well to group them together in the form of an appendix, under the above title.

Too often the student of nature, accustomed to the physiological aspect only of phenomena, and impressed with the importance of the function, regards reproduction as the only purpose of a difference of sex. He considers that the end is attained when the species is perpetuated, and may believe that could this be accomplished in any other mode, then sexuality would become a question of no moment.

The incorrectness of such a narrow view as this has been shown with extraordinary force of thought and beauty of language, by the eminent German philosopher and critic Wilhelm von Humboldt, in an essay on " The Difference of Sex and its Influence on Organic Nature."

We cannot enter here into the convincing and brilliant arguments which he adduces to prove the truth of his conclusions; we shall only repeat, in a brief and inadequate manner, what these conclusions are.

The distinction of sex, in his eyes, extends to the mental and moral as well as the physical traits. " Without it, nature would no longer be nature, her mechanism would cease, and both the attraction which draws individuals together, and the struggle which forces each to put forth his best energies, would cease, and a tedious, debilitating monotony would ensue."

The male is everywhere, and in all his manifestations, characterized by peculiar traits, and the female by others quite as much her own. The predominance of these qualities in either sex, however, is no advantage, but a disadvantage. In the highest types of human physical beauty, the feminine and masculine traits are brought into intimate union and a perfect equilibrium. In the Apollo of the Belvidere, magnificent specimen of manhood that it is, there is yet something feminine, something lends the grace and softness of the other sex to the powerful muscles and manly frame.

On the other hand, in that most perfect model of the female figure, the Venus of Milo, exquisitely feminine as it is, there lurks constantly some line or vague expression which reminds us of a man. Instinctively the ancient artist, with the divination of genius, recognized and gave to his work that unity of the sexes which the philosopher reasons must belong to the perfect human creature.

Let us exemplify our meaning by another and a loftier example. The traditional face of our Saviour, which is so familiar to us in Christian art, ancient and modern, it is well known is not a likeness, but an imaginary portrait, developed by the inspiration of ardent piety, and perfected by a long series of monastic artists, until it expresses the ideal of their highest art-dreams. And who, on attentively examining any good copy of this traditional face, can fail to be struck with the feminine softness and sweetness which are present, and which, though present, do not in the least weaken or deduct from the quiet decision, the unalterable serenity, the unmeasured power, and the masterly dignity of the countenance ?

What is in these lofty efforts of art portrayed in the physical powers is not less true of the intellectual and moral attributes. The remark has been made by some acute analyst of human nature, we believe by Goethe, that there is always something feminine in genius. Certainly that disposition is the most admirable, and that intellect most powerful, which include in themselves what we are accustomed to define as the masculine and feminine attributes, which temper the rude force of man with the delicate sensibilities of woman, which fortify her susceptible nature with his sterner strength.

These views, which we gather from the realms of art and philosophy, are not idle reveries. They have an immediate and most practical bearing on our own lives, on self-culture, on the education of youth, and on the relation of the sexes in early life.

An extended study of social life discloses to us two diverse theories which have prevailed, and still obtain in different nations, and in different families in the same nation, with reference to this topic.

The one holds that as early as possible in life, and for as long a time as possible, it is wise to separate the sexes and keep them separated.

The second theory insists that any such action is most inevitably calculated to defeat its objects, and to create and foster the very evils it is designed to avoid.

Let us examine these opinions.