city strabismus occurs, owing to the greater strength of the
muscles that carry the eyes inward.[124]

The facial expression which marks the culmination of tumescence,
and the approach of detumescence is that which is generally
expressive of joy. In an interesting psycho-physical study of the
emotion of joy, Dearborn thus summarizes its characteristics:
"The eyes are brighter and the upper eyelid elevated, as also are
the brows, the skin over the glabella, the upper lip and the
corners of the mouth, while the skin at the outer canthi of the
eye is puckered. The nostrils are moderately dilated, the tongue
slightly extended and the cheeks somewhat expanded, while in
persons with largely developed pinnal muscles the ears tend
somewhat to incline forwards. The whole arterial system is
dilated, with consequent blushing from this effect on the dermal
capillaries of the face, neck, scalp and hands, and sometimes
more extensively even; from the same cause the eyes slightly
bulge. The whole glandular system likewise is stimulated, causing
the secretions,--gastric, salivary, lachrymal, sudoral, mammary,
genital, etc.--to be increased, with the resulting rise of
temperature and increase in the katobolism generally. Volubility
is almost regularly increased, and is, indeed, one of the most
sensitive and constant of the correlations in emotional
delight.... Pleasantness is correlated in living organisms by
vascular, muscular and glandular extension or expansion, both
literal and figurative." (G. Dearborn, "The Emotion of Joy,"
_Psychological Review Monograph Supplements_, vol. ii, No. 5, p.
62.) All these signs of joy appear to occur at some stage of the
process of sexual excitement.

In some monkeys it would seem that the muscular movement which in
man has become the smile is the characteristic facial expression
of sexual tumescence or courtship. Discussing the facial
expression of pleasure in children, S.S. Buckman has the
following remarks: "There is one point in such expression which
has not received due consideration, namely, the raising of lumps
of flesh each side of the nose as an indication of pleasure.
Accompanying this may be seen small furrows, both in children and
adults, running from the eyes somewhat obliquely towards the
nose. What these characters indicate may be learned fro