THE GREAT ANTEATER. 123 



The structure of the thoracic and abdominal viscera will form the subject of a suc- 

 ceeding part of the present memoir. 



Salivary Glands. 



The glandular mass representing the submaxillary salivary glands in Man 

 (PI. XXXVII. fig. 1, a, a), is a biiobed body, sixteen inches in length, two inches in 

 greatest thickness at the posterior part which forms the isthmus or junction of the two 

 lobes or glands. From this confluent base they diverge, extending outwards and for- 

 wards, and form, each, a flattened triangular mass, from four to five inches in breadth 

 and two inches thick posteriorly, and becoming thinner towards the outer and anterior 

 border, where the apex is prolonged into a slender process. The isthmus, or base of 

 the combined glands, overlies the anterior half of the thorax ; the base of each lateral 

 lobe is notched by the prominence of the shoulder-joint (s, s), round which its outer 

 border extends ; the contracting anterior prolongations of the gland pass forwards 

 along the sides of the neck, external to the sterno-maxillares {w, w), and terminate a 

 little in advance of the angle of the jaw, at a'. 



The two packets of ducts {ib. h, b, figs. 1 & 2), which indicate the essential doubleness 

 of the gland, emerge from the inner and posterior part of the lateral lobes, five or six 

 inches in a straight line from the posterior border of the isthmus, and nine or ten inches 

 from the anterior attenuated extremity of the gland. After a short course, the ducts 

 dilate and form a small reservoir, ib. e, on each side ; they are here so closely covered 

 and connected by elastic cellular tissue as to seem a single reservoir ; they maintain 

 however their distinctness, and continue, contracted, from each dilatation, as three closely 

 united attenuated ducts, which at length unite into one long and slender duct. The 

 dilated portion is surrounded by a cornpressor muscle {constrictor salivaris, ib. fig. 3, k). 



The gland is conglomerate, the primary lobes being for the most part oblong, sub- 

 compressed, from about three to nine lines in diameter. The closely united ducts {d, d), 

 after quitting the reservoir, are continued forwards covered by the extraordinarily 

 extended mylohyoideus (g, h, i, j), and, after their union, the common duct terminates, 

 as above described, at the symphysis of the lower jaw (PI. XXXIX. fig. 3, d). 



The parotid gland {ib. fig. \, x) is small in proportion to the animal : it is situated 

 in front and below the root of the ear, is of a triangular form, two inches four lines in 

 length, one inch two lines in breadth, with the duct continued from the outer side of 

 the anterior apex of the gland, which apex terminates at the posterior end of the origin 

 of the masseter muscle. The duct {ib. y) extends forwards along the outside of the 

 masseter near its origin, passes along the buccinator near its upper border and beneath 

 the tendons of three of the retractors of the mouth, then dips under the orbicularis 

 oris {q, q), and terminates near the opening of the mouth. The length of the duct is 

 eleven inches, its diameter scarcely half a line. This is perhaps the longest duct, in 

 proportion to the size of the gland, in the animal kingdom. The depressor auris {w), 



t2 



