r
grappling irons), are found in the Papilionidae and are very
beautiful and varied, taking the forms of projecting claws,
hooks, pikes, swords, knobs, and strange combinations of these,
commonly brought to a keen edge and then cut into sharp teeth.

It is probable that all these structures serve to excite the
sexual apparatus of the female and to promote tumescence.

To the careless observer there may seem to be something vicious
or perverted in such manifestations in man. That opinion becomes
very doubtful when we consider how these tendencies occur in
people living under natural conditions in widely separated parts
of the world. It becomes still further untenable if we are
justified in believing that the ancestors of men possessed
projecting epithelial appendages attached to the penis, and if we
accept the discovery by Friedenthal of the rudiment of these
appendages on the penis of the human fetus at an early stage
(Friedenthal, "Sonderformen der menschlichen Leibesbildung,"
_Sexual-Probleme_, Feb., 1912, p. 129). In this case human
ingenuity would merely be seeking to supply an organ which nature
has ceased to furnish, although it is still in some cases needed,
especially among peoples whose aptitude for erethism has remained
at, or fallen to, a subhuman level.

At first sight the connection between love and pain--the tendency of men
to delight in inflicting it and women in suffering it--seems strange and
inexplicable. It seems amazing that a tender and even independent woman
should maintain a passionate attachment to a man who subjects her to
physical and moral insults, and that a strong man, often intelligent,
reasonable, and even kind-hearted, should desire to subject to such
insults a woman whom he loves passionately and who has given him every
final proof of her own passion. In understanding such cases we have to
remember that it is only within limits that a woman really enjoys the
pain, discomfort, or subjection to which she submits. A little pain which
the man knows he can himself soothe, a little pain which the woman gladly
accepts as the sign and forerunner of pleasure--this degree of pain comes
within the normal limits of love and is rooted, as we have seen, in the
experience of the race. But when it is carried beyond these limits, though
it may still be tolerated because of the support it receives from its
biological ba