Manhood: The Rise and Fall of the Penis (4 page)

A comparable situation exists with lizards of the genus
anolis
.

Some males remain as small as females and hence are not regarded as rivals by other males. They are able to move about the territory of larger male lizards unnoticed and mate with females. They must, though, keep a low profile, or they run the risk of unwanted homosexual contact.

Numbers tell the tale

The volume of a testicle can be estimated by using a tape measure and comparing the readings with plastic models of known volume. For adult men the volume usually exceeds 15 millilitres. A volume of between 17

and 25 millilitres is regarded as normal. The length varies from 3 to 6 cm, the width from 2 to over 3 cm. Large or small, these glands constitute an extremely ingenious production unit which every day turns out between ten and a hundred million ‘homunculi’, or tiny male creatures.

The volume and firmness of the testicle may indicate whether there are any endocrinal abnormalities. Small, rubbery testicles in a grown man, for example, may indicate insufficient stimulation. Before puberty the testicles are small, but the absence of a testicle from the scrotum is abnormal. It may be a case of a retractile testicle caused by the tensing of the testicular muscles, whereby the testicle is pulled in the direction of the external inguinal opening or even the inguinal canal. The medi -

cal term for this phenomenon is the cremaster reflex, which causes the sudden disappearance of the testicle!

The cremaster reflex may be triggered, for example, by stimulating the skin on the inside of the upper thigh. In older men the reaction is harder to provoke. The spiral-shaped fibres of the cremaster muscles run through the seminal cord to the base of the penis and when suddenly contracted may even result in testicular torsion. On the underside the testicle is attached to the scrotum by a wide band which normally prevents it from it turning vertically on its own axis.

22

t h e t e s t i c l e s a n d t h e s c ro t u m During sexual arousal engorgement with blood causes the testicle to increase in volume by up to 50 per cent. In the case of prolonged sexual arousal the accumulation of blood may cause pain (‘blue balls’), from which ejaculation brings relief. (Not that women should feel in any way responsible for this state of affairs!) Scientists in the German state of Thüringen were able to demonstrate that when the testicles of male ferrets swelled in spring, their brains also increased in size –

definitely not the case in humans!

Moving balls also seem to be an object of particular fascination for visual artists. Joop van Lieshout, for example, has produced a series of huge plastic penises, and in a tv programme he showed an excerpt from a work by his fellow-artist Bruce Nauman, who in 1969 filmed the dangling and bouncing of his own testicles with a high-speed camera, as part of a series of four
Slo Mo
films:
Black Balls
,
Bouncing Balls
,
Pulling Mouth
and
Gauze.

Nauman hired an industrial camera to film at very high speeds: the frame speed varied from 1,000 to 4,000 per second (the normal speed is 24 fps), in natural light. The shooting time was between four and six seconds, but the running time of
Bouncing Balls
is nine minutes. The extreme slow-motion effect means that movement is sometimes scarcely perceptible.

Leydig and Sertoli cells

Each of the two testicles – separated from each other in the scrotum by a membrane, the septum – is made up of two compartments. In terms of volume 95 per cent of the testicle is devoted to sperm production.

There are approximately 250 lobules, and if you were to lay all the tubes in the lobules end to end they would have a combined length of about 500 metres. The inner wall of the tubes contains germ cells which after a process of divisions produce young but not yet mature sperm cells.

Between ten and a hundred million sperm cells are produced every day.

The unbelievably dense network of fine seminal tubes constituting the sperm-producing section of the testicles was described in the seventeenth century by Reinier de Graaf, though the actual discovery was made by De Graaf’s teacher, Professor Johannes van Horne of Leiden University. During a study placement in France De Graaf had used bull’s testicles for his research. These were easily obtainable, but turned out to be less than ideal for research purposes. He finally opted for the testicles of an unusual little creature, the dormouse. Its body weight is approximately 100 g and the testicles weigh about 1 g each.

De Graaf removed the outer membrane from the dormice testicles and 23

m a n h o o d

then submerged them in a glass of water. When the glass was gently shaken the testicles simply fell to pieces. ‘One can clearly see that the testicles consist wholly of tiny tubes,’ wrote De Graaf in his book (Van Horne had previously stated that the testicle was nothing but ‘a collection of tiny threads’). This was in fact plagiarism by De Graaf, but after a long correspondence with the Royal Society he was credited with the discovery of the ‘threads’. For the sake of completeness he even had to forward a dissected dormouse testicle that he had preserved in alcohol.

Back to anatomy. Between the tubes, the ‘threads’ in which the sperm cells are formed, there are blood vessels, the Sertoli cells and the Leydig cells. The Sertoli cells, the support cells, form part of the blood-testicle barrier, controlling the emergence of the mature sperm cells: all nutriment for the maturing spermatozoa must first pass through them.

The Italian physiologist Enrico Sertoli (1842–1910) was still a medi -

cal student when he observed these ‘nurse’ cells in 1862. In the young embryo they make the Anti-Müllerian hormone (the Müllerian duct produces female sex organs, the Wolffian duct male ones), which ensures that the male embryo actually acquires normal sexual characteristics. After puberty the Sertoli cells produce the hormone inhibine.

The Leydig cells, named after the German anatomist Franz von Leydig (1842–1910), make up approximately 5 per cent of the total volume of the testicles, and use cholesterol to produce, from puberty onwards, about 7 milligrams per day of the male sex hormone testosterone. They do this in response to the lh (luteinizing hormone) transmitted by the hypophysis or pituitary gland at the base of the brain.

Sertoli cell

Spermatogenesis

Microscopic

Leydig cell

image of testi -

cular tissue.

t h e t e s t i c l e s a n d t h e s c ro t u m The course of the

ductus ferens.

Ductus deferens

Verumontanum

Another regulating substance transmitted by the hypophysis is the Follicle Stimulating Hormone (fsh), which regulates sperm cell formation.

The seminal duct (the
ductus deferens,
or
vas deferens
) runs for a distance of between 30 and 40 cm from the epididymis to the
verumontanum
, an elevation or crest in the wall of the urethra in the centre of the prostate.

Also near the prostate, behind the bladder, are the two seminal glands (
vesiculae seminalis
), which despite what their name suggests do not store sperm cells but produce fluid, part of the transport medium for the sperm cells. After all, in an ejaculation it is not only sperm cells that are expelled. An ejaculate consists in large part of fluid originating from the seminal glands and the prostate. The sperm cells account for only a small percentage of the total volume. In older medical literature a distinction is made between the section of the sperm cell constituting the ‘noblest part’, the ‘aqueous elements’ from the seminal glands, and the ‘oleagenous’ section from the prostate.

In the late 1950s Japanese researchers conducted experiments with x-ray contrast media that showed clearly how the different sections emerged. First sperm cells were forced from the epididymis in the direction of the ampoule of the seminal duct. The ampoule is a protuberance close to the spot where the seminal duct discharges, in which a quantity of sperm can be stored. Then the muscles around the seminal glands contract, and the sperm cells with fluid originating from the seminal glands are forced together into the prostatic section of the urethra, where they are mixed with prostate liquid. One striking feature is that some sperm cells also return to the ampoule and seminal glands.

25

m a n h o o d

The seminal glands particularly contain many nooks and crannies where sperm cells can linger for a considerable period. A practical result of this is that for a long time after sterilization sperms may sometimes be visible in the ejaculate.

The smell and taste of sperm

Women often compare the smell of sperm to plant or flower scents.

Herb Robert (
Geranium robertianum
), St John’s wort (
Hypericum
perforatum
), the flowers of the European barberry (
Berberis vulgaris
) and chestnuts all smell of sperm. The same applies to the crushed flowers of the henna plant (
Lawsonia inermis
). Moroccan women love rubbing them into their palms, while Western European women use them, often in powder form, to dye their hair.

Billy-goats, long regarded as the epitome of animal horniness, spray their own beards with sperm and urine. The Ancient Greeks dreamt up all kinds of hybrids of man and billy-goat, such as the demi-god Satyr and the forest god Pan, and the physical attributes of these sensuous figures (horns, hoofs and beard) were adopted by Christianity to depict the Devil. Billy-goats, however, have some surprisingly female aspects.

If one massages their nipples for an extended period, a milk-giving udder appears in front of the scrotum!

The American jazz musician Charles Mingus compared the texture of sperm to cream: ‘She gulps and slurps the cream out of me while I melt and she sucks hard at my tree.’ John Hunter, a nineteenth-century English surgeon, observed in one of his essays that ‘if one holds sperm in one’s mouth it gives a warmth like spices’. The celebrated sexologist Havelock Ellis (1859–1939) wrote that many primitive peoples, particularly the Australian aborigines, made potions from sperm, which were given to sick or dying members of the tribe. In addition he mentions the Manicheans and the Albigensians, who sprinkled the bread used for Holy Communion with human sperm. In the seventeenth century sperm was regarded as an effective defence against witchcraft and a precious aphrodisiac. The church, however, refused to tolerate it, and in his book Ellis records prison sentences of seven years for the offence.

According to reliable sources it is not unusual for young women today in a get-together in the pub to admit whether they ‘swallow’ or not. They’re not talking about E, amphetamines or suchlike, but whether or not they swallow sperm. There is some similarity between suckling and fellatio, between mother’s milk and sperm: just as an infant can taste whether its mother has eaten garlic, a woman who

‘swallows’ can taste the garlic that her partner has eaten the day before.

Sperm is both stronger in flavour and more bitter if a man smokes and 26

t h e t e s t i c l e s a n d t h e s c ro t u m drinks a lot of coffee, while the sperm of vegetarians reputedly tastes better than that of carnivores. Kiwi fruit particularly are supposed to improve the flavour. A famous (male) Dutch comic duo felt that truly emancipated women should immediately spit the sperm out again. I can’t remember why, nor do I have any ready-made answer on the subject. I do know, though, that only three men in every thousand can suck themselves off.

While we are talking about ejaculation and secretion, this is the place to mention in passing the glands about which the English physician William Cowper was the first to publish in 1702, situated a little upstream of the prostate and also issuing into the urethra, which in a state of arousal produce the so-called preseminal fluid. In women the corresponding glands are named after the Danish researcher Bartholin (1585–1629).

The smell of the scrotum

The degree of hirsuteness and the smell of the scrotum vary – a topic that was raised as early as the 1870s in the work of the American feminist novelist and campaigner Lois Waisbrooker (1826–1909). Some of today’s racy pulp novelists, one feels, should have been made to study Erica Jong’s
Fear of Flying
(1974) as prescribed reading. In the latter book, with disarming frankness and great literary panache, Jong (1942–) evokes the physical attributes of her lovers, ephemeral and more significant: