[ 1063 ] 
XXV. The Minute Anatomy of the Thymus. 
By Herbert Watney, M.A., M.D., Cantab., Joint Lecturer on Physiology 
at St. George’s Hospital. 
Communicated by E. A. Schafer, F.R.S ., Assistant Professor of Physiology in 
University College, London. 
Received January 30,—Read February 16, 1882. 
[Plates 83-95.] 
Table of Contents. 
Page 
Preliminary statement.. 1064 
History . 1064 
History of the views concerning the development of the thymus ........ 1073 
Opinions of various authors concerning the so-called plasma cells .. 1074 
The methods used. 1075 
Staining by means of hgematoxylin extract .. 1075 
Staining by means of extract of Brazil wood. 1077 
General observations. 1077 
Anatomy of the follicle as a whole. 1078 
The lymphatics of the thymus . 1081 
The blood vessels. (See also p. 1097). 1082 
The tissues composing the cortical portion of the follicle. 1083 
The tissues composing the medullary portion of the follicle. 1084 
Granular cells. 1085 
Giant cells. 1088 
Concentric corpuscles . 1088 
Ciliated epithelium in the thymus of the Dog. 1092 
Changes in the thymus during involution . 1094 
Formation of fibrous tissue within the follicle. .. 1095 
Growth of the interfollicular tissue, and invasion of this tissue into the 
follicle.—Plasma cells and formation of fat .'.. 1096 
Changes in the vessels. 1097 
The thymus of Birds, Reptiles, Amphibia, and Fish... 1097 
Thymus of the Bird...,. 1098 
Thymus of the Reptile .. 1099 
Thymus of Amphibia. 1100 
Thymus of Fish. 1100 
Development. 1101 
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MDCCCLXXX1I. 
