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ANATOMY] chief application of the word is, however, to various objects used in funeral ceremonies. A “herse” or “hearse” seems first to have been a barrow-shaped framework of wood, to hold lighted tapers and decorations placed on a bier or coffin; this later developed into an elaborate pagoda-shaped erection of woodwork or metal for the funerals of royal or other distinguished persons. This held banners, candles, armorial bearings and other heraldic devices. Complimentary verses or epitaphs were often attached to the “hearse.” An elaborate “hearse” was designed by Inigo Jones for the funeral of James I. The “hearse” is also found as a permanent erection over tombs. It is generally made of iron or other metal, and was used, not only to carry lighted candles, but also for the support of a pall during the funeral ceremony. There is a brass “hearse” in the Beauchamp Chapel at Warwick Castle, and one over the tomb of Robert Marmion and his wife at Tanfield Church near Ripon.

 HEART, in anatomy.—The heart is a four-chambered muscular bag, which lies in the cavity of the thorax between the two lungs. It is surrounded by another bag, the pericardium, for protective and lubricating purposes (see ). Externally the heart is somewhat conical, its base being directed upward, backward and to the right, its apex downward, forward and to the left. In transverse section the cone is flattened, so that there is an anterior and a posterior surface and a superior and inferior border. The superior border, running obliquely downward and to the left, is very thick, and so gains the name of margo obtusus, while the inferior border is horizontal and sharp and is called margo acutus (see fig. 1). The divisions between the four chambers of the heart (namely, the two auricles and two ventricles) are indicated on the surface by grooves, and when these are followed it will be seen that the right auricle and ventricle lie on the front and right side, while the left auricle and ventricle are behind and on the left.

The right auricle is situated at the base of the heart, and its outline is seen on looking at the organ from in front. Into the posterior part of it open the two venae cavae (see fig. 2), the superior (a) above and the inferior (b) below. In front and to the left of the superior vena cava is the right auricular appendage (e) which overlaps the front of the root of the aorta, while running obliquely from the front of one vena cava to the other is a shallow groove called the sulcus terminalis, which indicates the original separation between the true auricle in front and the sinus venosus behind. When the auricle is opened by turning the front wall to the right as a flap the following structures are exposed:

1. A muscular ridge, called the crista terminalis, corresponding to the sulcus terminalis on the exterior.

2. A series of ridges on the anterior wall and in the appendage, running downward from the last and at right angles to it, like the teeth of a comb; these are known as Musculi pectinati.

3. The orifice of the superior vena cava (fig. 2, a) at the upper and back part of the chamber.

4. The orifice of the inferior vena cava (fig. 2, b) at the lower and back part.

5. Attached to the right and lower margins of this opening are the remains of the Eustachian valve (fig. 2, h), which in the foetus directs the blood from the inferior vena cava, through the foramen ovale, into the left auricle.

6. Below and to the left of this is the opening of the coronary sinus (fig. 2, k), which collects most of the veins returning blood from the substance of the heart.

7. Guarding this opening is the coronary valve or valve of Thebesius.

8. On the posterior or septal wall, between the two auricles, is an oval depression, called the fossa ovalis (fig. 2, g), the remains of the original communication between the two auricles. In about a quarter of all normal hearts there is a small valvular communication between the two auricles in the left margin of this depression (see “7th Report of the Committee of Collective Investigation,” J. Anat. and Phys. vol. xxxii. p. 164).

9. The annulus ovalis is the raised margin surrounding this depression.

10. On the left side, opening into the right ventricle, is the right auriculo-ventricular opening.

11. On the right wall, between the two caval openings, may occasionally be seen a slight eminence, the tubercle of Lower, which is supposed to separate the two streams of blood in the embryo.

12. Scattered all over the auricular wall are minute depressions, the foramina Thebesii, some of which receive small veins from the substance of the heart.

The right ventricle is a triangular cavity (see fig. 2) the base of which is largely formed by the auriculo-ventricular orifice. To the left of this it is continued up into the root of the pulmonary artery, and this part is known as the infundibulum. Its anterior wall forms part of the anterior surface of the heart, while its posterior wall is chiefly formed by the septum ventriculorum,