THE FRAMEWOEK OF THE GLANDULA PAEATHYROIDEA. 



BY 



JOSEPH MARSHALL FLINT, M. D. 



From the Hearst Anatomical Laboratory of the University of California. 



With 3 Text Figures. 



In studying the framework of the thyroid gland in man and the 

 higher mammals, the author was enabled at the same time to make cer- 

 tain observations concerning the supporting tissue of the glandula para- 

 thyroidea. These investigations were carried oi; by means of the de- 

 structive digestive methods through which the cytoplasmic elements are 

 all 'dissolved, leaving the resistant framework of the organ in the form of 

 an opaque skeleton, which reveals its original form and relationships, 

 and demonstrates clearly at the same time, the course of the various 

 interstitial processes in three dimensions of space. The details of the 

 method have already been published in another place.^ In both the 

 monkey and the dog the parathyroid bodies are situated within the general 

 capsule of the glandula thyroidea. Under normal conditions in both the 

 living organ and in fixed tissues, the small oval gland is scarcely elevated 

 from the surface of the larger organ in which it is contained. The 

 fasciculated capsule of the thyroid practically splits and embraces the 

 gl. parathyroidea which is oval in both longitudinal and transverse 

 dimensions. Accordingly the capsule of the thyroid becomes the capsule 

 of the parathyroidea, with no essential differences in structure. Like the 

 capsules of most organs it is composed of laminated fasciculi of white 

 fibrous tissue, with a considerable amount of reticulum in its inner 

 surface. This capsule contains a small amount of elastic tissue, some of 

 which may accompany the larger septa that follow the greater vessels 

 into the substance of the gland. In piece digestions which have been 

 cut through the thyroid and parathyroid, the organ is clearly shown in 

 three dimensions. In both dog and monkey, the parathyroid is 2|- mm. 

 broad, about 4 mm. long, and about 2 mm. in thickness. When viewed 

 with a stereoscopic microscope, the organ is seen just within the capsule 



'Flint: Bulletin of the Johns Hopkins Hospital, 1901; Arch. f. Anat. u. 

 Ent. Anat. Abth., 1903. 



AMKRICAN JOUIiNAL OF ANATOMY.- — VOL. IV. 



