begotten of the seed, which are bones, gristles, ligaments,
membranes, nerves, arteries, veins, skins, fibres or strings, fat.

_Bones_.] The bones are dry and hard, begotten of the thickest of the seed,
to strengthen and sustain other parts: some say there be 304, some 307, or
313 in man's body. They have no nerves in them, and are therefore without
sense.

A gristle is a substance softer than bone, and harder than the rest,
flexible, and serves to maintain the parts of motion.

Ligaments are they that tie the bones together, and other parts to the
bones, with their subserving tendons: membranes' office is to cover the
rest.

Nerves, or sinews, are membranes without, and full of marrow within; they
proceed from the brain, and carry the animal spirits for sense and motion.
Of these some be harder, some softer; the softer serve the senses, and
there be seven pair of them. The first be the optic nerves, by which we
see; the second move the eyes; the third pair serve for the tongue to
taste; the fourth pair for the taste in the palate; the fifth belong to the
ears; the sixth pair is most ample, and runs almost over all the bowels;
the seventh pair moves the tongue. The harder sinews serve for the motion
of the inner parts, proceeding from the marrow in the back, of whom there
be thirty combinations, seven of the neck, twelve of the breast, &c.

_Arteries_.] Arteries are long and hollow, with a double skin to convey the
vital spirit; to discern which the better, they say that Vesalius the
anatomist was wont to cut up men alive. [958]They arise in the left side of
the heart, and are principally two, from which the rest are derived, aorta
and venosa: aorta is the root of all the other, which serve the whole body;
the other goes to the lungs, to fetch air to refrigerate the heart.

_Veins_.] Veins are hollow and round, like pipes, arising from the liver,
carrying blood and natural spirits; they feed all the parts. Of these there
be two chief, _Vena porta_ and _Vena cava_, from which the rest are
corrivated. That _Vena porta_ is a vein coming from the concave of the
liver, and receiving those mesaraical veins, by whom he takes the chylus
from the stomach and guts, and conveys it to the liver. The other derives
blood from the liver to nourish all the other dispersed members. The
branches of that _Vena porta_ are the mesaraical and haemorrhoids. The
branches of the _cava_ are inward or outward. Inward, seminal or emulgent.