128 PROFESSOR OWEN ON THE ANATOMY OF 
Sternoglossus.—This remarkable muscle arises fleshy from the lateral border of the 
dilated xiphoid and last sternal bone, and from its junction with the last two true ribs. 
The origin (Pl. XXXVIII. fig. 2, e) is at first triangular, but soon assumes a flattened 
shape, six lines broad by two lines thick, the muscle gradually diminishing in breadth, 
as it extends forwards, without losing thickness. Linear tendinous intersections (ib. f, f) 
mark the part of the muscle within the chest; the first occurs about two inches and 
a half from the origin, and is bent with the angle turned forward ; the second, about 
two inches in advance, crosses the muscle obliquely; the third, at about the same 
interval, sends a slight angle forward; the fourth is an angular intersection, with the 
point turned backward on one side and forward on the other side of the muscle. 
From this point the sternoglossus passes forward, emerging from beneath the manu- 
brium sterni as a simple fleshy muscle (Pl. XX XVIII. figs. 1 & 2, g), five lines broad 
and from two to three lines thick. Opposite the hyoid it is perforated by a lingual 
artery: between four and five inches in advance it is perforated by the lingual nerve 
(<b. fig. 1, u,v); and here it begins to give off, or its inferior stratum is resolved into, 
flattened fasciculi of fibres which decussate or combine with those of the opposite 
muscle, h,h. About six inches in advance of the basihyal these fasciculi spread over a 
dilated membranous portion of the buccal cavity, at the lower part of which the base 
of the tongue is situated: and here they converge and blend with corresponding flattened 
fasciculi, o', o', sent off from the lower part of the genioglossi, as these pass backward to 
the base of the tongue. The main continuation of the sternoglossus, which is concealed 
by the subgular fasciculi, forms a rounded slender muscle (i, i, fig. 2), which raises the 
buccal membrane so as to form the back part of the fraenum lingue, and penetrates, 
or forms, the back part of the base of the tongue, and a great proportion of its sub- 
stance. 
Genioglossus.—This muscle (Pl. XX XVIII. m, n, 0) has a complex origin, by a middle 
portion, from the short symphysis mandibule, m, and by a flattened penniform series 
of fibres, from the lower border of the mandibular rami for the extent of four inches 
behind the symphysis, n,n. The symphysial origin is round and slender, and belongs 
more directly to the proper tongue-muscle: the ramal origins seem to be the more 
special fixed point of the subgular fasciculi. The fibres of the ramal origin, n, n, 
pass obliquely backward and inward, converging to a middle raphé, to which the 
symphysial origin closely adheres. The two origins of the muscle are blended into one 
for about three inches beyond the point of attachment, in which extent the muscle 
forms a moderately thick depressed mass along the middle of the under part of the 
mouth. It then begins to expand, and to detach from its under surface those subgular 
fasciculi, o', o', which diverge and unite with the corresponding dismemberments, h, h, 
of the sternoglossi. The main part of the genioglossus enters, as a single muscle (ib. 
fig. 2, 0), the fore part of the base of the tongue, carrying into the floor of the mouth 
a fold of buccal membrane forming the fore part of the freenum lingue. Between the 
