2024 Journal of Applied Microscopy 



NORMAL AND PATHOLOGICAL HISTOLOGY. 



JOSEPH H. PRATT, Harvard University Medical School. 



Books for Review and Separates of Papers on these Subjects should be Sent to Joseph H. Pratt, 

 Harvard University Medical School, Boston, Mass. 



..,.,., ^^ , , ^ , In every case of myelogenous leukae- 



michaelis, L. Ueber emem der Gnippe der , ■' .7 



Leukamie-artigen Erkrankungen zugehori- mia the blood contains, in addition tO 

 gen Fall. Zeitschrift fiir klin. Med. 45: neutrophilic and eosinophilic myelo- 

 87-96, 1902. ^ ^ ■' 



cytes and mast-cells, also non-granular 



cells with a small amount of protoplasm. These cells are present in considerable 

 number and are generally looked upon as lymphocytes. Michaelis, however, 

 regards them as undifferentiated lymphoid cells. They cannot be distinguished 

 morphologically from lymphocytes. The undifferentiated lymphoid cells by 

 further development become transformed into neutrophilic myelocytes, while the 

 lymphocytes are adult cells. 



The undifferentiated lymphoid cell differs from Benda's " myelogenic " cell 

 in that the former develops not only in the bone-marrow but in other tissues. 



Michaelis supports his view by a remarkable case of disease of the blood- 

 forming organs which came under his observation. The total number of leuco- 

 cytes in the peripheral circulation was only slightly increased, but T<i per 

 cent, of the cells were lymphocytes and 7 per cent, myelocytes. The patient 

 died after an illness of three months. The lymph-nodes were not swollen. The 

 spleen was very large and soft and weighed 2000 grams. The bone-marrow 

 was red and consisted almost entirely of lymphocytes and giant-cells. The 

 spleen had the same histological structure. j. h. p. 



Robinson, G. C. On a Cyst Originating from Cysts in the regio-thyroidea have been 



the Ductus Thyreoglossus. J. H. Hosp. discussed by Verneuil, who collected a 

 Bull. 8: 81-82, 1902. , / ^ .u r. * 



^ number of cases from the literature. 



He found several bursae in the thyro-hyoid region, and thought cysts might come 

 from them. The origin of one cyst, previously described, he attributed to the 

 cystic dilatation of the pyramidal prolongation of the thyroid towards the hyoid. 

 In the development of the thyroid the ductus thyreoglossus, which is lined 

 by ciliated epithelium, is cut off in its upper portion to form the blind lingual 

 duct, while its lower portion forms the ductus thyroideus. Cysts have been de- 

 scribed in both these portions, and even in the portion of the duct enclosed in 

 the hyoid bone. Robinson relates a case. The patient had a rounded swelling 

 in the median line of the neck, just above the thyroid region. Fluctuation 

 could be detected on palpation. At autopsy the tumor was found to be a spher- 

 ical, unilocular cyst about 4^ cm. in diameter. It lay upon and was lightly 

 attached to the sterno-hyoidei muscles. By a narrow aberrant band of muscle 

 it was connected with the lower surface of the body of the hyoid bone. On sec- 

 tion its contents included a glairy mucoid fluid with a mass of cellular detritus. 

 The lining surface was smooth and velvety. Microscopically *he wall was com- 

 posed of compact laminated connective tissue, with generally a lining cell, of a 

 single layer of high columnar epithelium. No thyroid tissue was found, but 

 from its position and lack of connection with either the trachea or pharynx, the 

 given origin of the cyst seems most likely. w. r. s. 



