The anatomy of humane bodies epitomized wherein all parts of man's body, with their actions and uses, are succinctly described, according to the newest doctrine of the most accurate and learned modern anatomists / by a Fellow of the College of Physicians, London.

CHAP. XX.

Of the Vasa praeparantia in Man.

HItherto we have handled the parts appointed for nutrition, whereby the nutriments are prepared in the lower Belly for the sustentation of an individual body: Now we come to the organs of generation, whereby through procreation is conserved a perennity of Mankind, which Nature hath denied to particulars. These parts being not alike in both Sexes, we must necessarily treat of each apart, and first of those of Men.

In Man some of these parts afford matter for the Seed, to wit, the Arteriae spermaticae; others bring back again the Bloud that is superflous to the making of the Seed and to the nourishment of the Testicles, and these are the Venae spermaticae; and both the Arteries and Veins were formerly called Vasa praeparantia: some make the Seed, as the tones: some carry the Seed back again, as those which are called Vasa deferentia: some con∣tain the Seed, and an oleaginous matter, as the Vesiculae seminales the first, and the Prostates the latter: some discharge the Seed into the Matrix; this is done by the Penis.

Vasa praeparantia, which are said to prepare matter for the Seed, are of two sorts, Arteries, and Veins.

The Arteries are two, and spring from the Trunk of the Aorta, commonly two fingers breadth under the Emulgents, not just from its side but out of its fore-part, the right whereof climbing over the trunk of the Vena cava, runs obliquely to the Vein of the same side; as also the left, marches to the Vein of that side.

The Veins are also two. The right arises usu∣ally from the trunk of Vena cava, a little below the Emulgent; the left from the Emulgent it self, for otherwise it must have gone over the Aorta, whereby it might have been in danger of breaking; or rather by the continual pulse of the Artery the recourse of the Venal bloud might have been retarded. Now both these Veins and Arteries a little after their rise meet, and are in∣vested both in one Membrane made of the Perito∣naeum, and then run streight through the region of the Loins above the Muscles Psoae on each side, and above the Ureters, as they go bestowing lit∣tle slips here and there upon the Peritonaeum, be∣tween whose duplicature they descend, and so arrive at its processes. The Veins divide very often into many branches, and by and by inoscu∣late and unite again; but the Arteries go along by one Pipe only, on each side, untill within three or four fingers breadth of the Stones, where each is divided into two branches, the less where∣of runs under the Epididymis, the larger to the Testicle. And as I said they descended betwixt the Membranes of the Peritonaeum, so they pass in∣to the Scrotum between them, not perforating them in the processes, as in Dogs and other Creatures, wherein the processes of the Peritonae∣um are hollow like a Quill; but in Man the inner

Membrane of the Peritonaeum shuts the hole lest the Intestins fall by it into the Cod; of which there is great danger in him (and we see it often hap∣pen) because of his going upright. But to re∣turn to the Vasa praeparantia. It has been gene∣rally taught that there are divers inosculations of the Arteries with the Veins in their passage, whereby the Venal and Arterial bloud are mixed; but this opinion is now exploded, for that, granting the circulation of the Bloud, it is impossible. For the Bloud in the Arteries de∣scends towards the Testicles, and that in the Veins ascends from them, so that if these two Vessels should open one into the other, the Bloud in one of them must needs be driven back, or else, stagnating, distend and break the Vessels. But the truth is, the Bloud both for the nourishment of the Testicles and the making of Seed flows down by the Arteries only, and that in an even undivided course, without any of those windings and twirlings like the Tendrels of Vines talkt so much of, (as the curious de Graef by his own fre∣quent inspection testifies:) But the Veins bring back from the Testicles what of the Bloud remains from their nourishment and making of Seed, and these indeed come out of the Testicles by almost innumerable roots by which they imbibe the said Bloud, and are most admirably interwoven and inosculated one with another till about four or five fingers breadth above the Testicle, which space is called Corpus pyramidale, Plexus pampini∣formis, or Varicosus; but these Veins are so far from preparing the Seed, as that they only bring back what was superfluous from the making of it. And indeed the Arteries in Men do no more merit

the name of Praeparantes in respect to the Seed, than the Gullet in respect of the Chyle, or the Ductus thoracicus chyliferus in regard to the Bloud. But however, we continue the old names, decla∣ring only against the reason of them. And we will only note two things more. First, that these Spermatick veins have from their rise to their end several Valves which open upwards, and so suffer the Bloud to ascend towards the Cava, but not to slide back again. Secondly, that though the Spermatick Arteries go such a direct course in Men, as has been said; yet in Brutes they are more complicated and twisted with the Veins, but without any anastomoses of one into the other.

There are Nerves and Lympheducts that pass into the Testicles together with these Vasa praepa∣rantia; of which in the next Chapter.

Notes

• The parts of the geni∣tals in man.
• Vasa prae∣parantia.
• Arteries.
• Veins.