14 52 THE DUCTLESS GLANDS 



THE CAROTID GLANDS, OR CAROTID BODIES (GLOMUS 



CAROTICUM). 



The carotid bodies, two in number, are situated one on either side of the neck, 

 behind the common carotid artery at its point of bifurcation into the internal and 

 external carotid trunks. They are reddish brown in color and oval in shape, 

 the long diameter measuring about one-fifth of an inch (5 mm.) Each is invested 

 by a fibrous capsule and consists of spherical or irregular masses of cells the 

 masses being more or less isolated from each other by septa which extend inward 

 from the capsule. A network of large capillaries from the carotid artery ramifies 

 among the cell masses, together with numerous sympathetic nerve fibres. The 

 cells are polyhedral in shape, and each contains a large nucleus embedded in 

 finely granular protoplasm which is stained yellow by chromic salts. 



Applied Anatomy. Tumors may arise from this structure. Such a tumor is apt to be 

 above the level of the upper margin of the thyroid cartilage, and in most cases it moves with 

 each arterial beat. 



THE COCCYGEAL GLAND OR BODY, OR LUSCHKA'S GLAND 

 (GLOMUS COCCYGEUM). 



Lying near the tip of the coccyx in a small tendinous interval formed by the 

 union of the Levator ani muscles and just above the coccygeal attachment of the 

 Sphincter ani is a small conglobate body about as large as a millet seed, first 

 described by Luschka, and named by him the coccygeal gland. Its most obvious 

 connections are with the middle sacral artery. 



Structure. It consists of a congeries of small arteries with little aneurismal dilatations 

 derived from the middle sacral and freely communicating with each other. The gland is sur- 

 rounded by a capsule of white fibrous connective tissue which sends in septa to form the frame- 

 work of the organ and to divide it into spaces which contain groups of polyhedral cells. Each 

 cell contains a large round or oval nucleus, the protoplasm surrounding which is clear and is 

 not stained by chromic salts. 1 Nerves pass into this little body from the sympathetic, but 

 their mode of termination is unknown. Macalister believes the glomerulus of the vessels "con- 

 sists of the condensed and convoluted metameric dorsal arteries of the caudal segments em- 

 bedded in tissue which is possibly a small persisting fragment of the neurenteric canal." 



THE PARASYMPATHETIC BODIES (ORGANA PARASYMPATHETICA 



OF ZUCKERKANDL). 



The parasympathetic bodies were discovered in 1901 by Zuckerkandl. They are 

 from one to four in number, situated retroperitoneally, ventrad of the abdominal 

 aorta at the level of the third and fourth lumbar vertebra?. Each parasympathetic 

 body is from 6 to 10 mm. in length and from 2 to 4 mm. in width, and is surrounded 

 by a capsule of fibrous tissue. In the meshes of the reticulum are found groups 

 of polyhedral or cuboidal epithelial cells, closely packed and of the chromaffin 

 type. These bodies are usually supplied by fine arterial twigs from the aorta. 

 They are best developed in the fetus and in infancy. 



1 Consult J. W. T. Walker, "Ueber die menschliche Steissdruse," Arch. f. mikr. Anat. u. Entwickgesch., 1904. 



