odies of indefinite and changing
shape, and having a central brighter portion, the nucleus with a still
brighter dot therein the nucleolus-- the white corpuscles (w.c.), and

(3.) flat round discs, without a nucleus, the red corpuscles (r.c.),
greatly more numerous than the white.

Section 36. The chyle of the lacteals passes, as we have said, by
the thoracic duct directly into the circulation. It enters the left vena
cava superior (l.v.c.s.) near where this joins the jugular vein (ex.j.)
(see Figure 1, Sheet 2, th.d.) and goes on at once with the rest of
the blood to the heart. The small veins of the villi, however, which also
help suck up the soluble nutritive material, are not directly
continuous with the other body veins, the systemic veins; they
belong to a special system, and, running together into larger and
larger branches, form the lieno gastric (l.g.v.) and mesenteric (m.v.)
veins, which unite to form the portal vein (p.v.) which enters the liver
(l.v.) and there breaks up again into smaller and smaller branches.
The very finest ramifications of this spreading network are called the
(liver) capillaries, and these again unite to form at last the hepatic
vein (h.v.) which enters the vena cava inferior (v.c.i.), a median
vessel, running directly to the heart. This capillary network in the
liver is probably connected with changes requisite before the
recently absorbed materials can enter the general blood current.

Section 37. The student has probably already heard the terms vein
and artery employed. In the rabbit a vein is a vessel bringing blood
towards the heart, while an artery is a vessel conducting it away.
Veins are thin-walled, and therefore flabby, a conspicuous purple
when full of blood, and when empty through bleeding and collapsed
sometimes difficult to make out in dissection. They are formed by
the union of lesser factors. The portal breaks up into lesser branches
within the liver. Arteries have thick muscular and elastic walls, thick
enough to prevent the blood showing through, and are therefore pale
pink or white and keep their round shape.

Section 38. The heart of the rabbit is divided by partitions into four
chambers: two upper thin-walled ones, the auricles (au.), and two
lower ones, both, and especially the left, with very muscular walls,
the ventricles (vn.). The right ventricle (r.vn.) and auricle (r.au.)
communicate, and the left ventricle (l.vn.) and auricle (l.au.).