The head or glans of the clitoris is roughly the size and shape of a pea, although it can be significantly larger or smaller. The clitoral glans is highly sensitive, containing as many nerve endings as the analogous organ in males, the glans penis, but concentrated in a smaller surface, thus making it particularly well-suited for sexual stimulation. During arousal, the glans becomes engorged with blood and sometimes protrudes outside from the clitoral hood or bulging under it.
^Handbook of Psychophysiology By John T. Cacioppo, Louis G. Tassinary, Gary G. Berntson Contributor John T. Cacioppo, Louis G. Tassinary, Gary G. Berntson Edition: 3, illustrated, revised Published by Cambridge University Press, 2007 ISBN 0-521-84471-1, ISBN 978-0-521-84471-0 898 pages pp 246-247.
^Masters, Johnson, William and Virginia (1988). Sex and Human Loving. Little, Brown & Company. ISBN0-316-50160-3.