and Laboratory Methods. '2435 



stance is used as the dart poison without further admixture. The active principle 

 of the sap is a crystalline nitrogen-free glucoside having the formula 

 CgiHg^Oj, and called antiarin. The physiological action of ipoh on frogs is 

 to produce clonic spasms of the muscles, paralysis, and systolic arrest of the 

 ventricle. The injection of a solution of the crystallized antiarin produces the 

 same results except that the clonic spasms are absent. With mannuals and 

 some birds the same effects are produced and in addition there are marked 

 gastro-intestinal symptoms, e. g., profuse diarrhcea. It was found that certain 

 birds, notably fowls and pheasants, possess a high degree of natural immunity to 

 this poison. This is thought to be due to a greater power of resistance of the 

 heart muscle in these cases. r. p. 



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. 



V • ,- A n I TT 1 J A r The writers have discovered by means 



Kaiserling and Orgler. Ueber das Auftreten ^ 



von Myelin in Zellen und seine Beziehung of the polariscope a double refractive 



zur Fettmetamorphose. Virchow's Archiv, substance in cells which resembles fat 

 107 : 296, 1902. 



morphologically. They hold that it is 



identical with the myelin described by Virchow. Hence this name is retained. 

 The droplets are stained light gray by osmic acid, never coloring as intensely ns 

 fat. With Sudan III or scharlach R they take a red hue. Myelin stained with 

 osmic acid, unlike fat, is decolorized by xylol, chloroform, and oil of bergamot. 

 In hardened tissues the double refraction of the myelin is lost. Myelin droplets 

 were found in the intima cells of arteries in fatty metamorphosis, particularly 

 in the aorta, in an amyloid kidney, and a great white kidney of chronic Bright's 

 disease, in the epithelial cells of the pulmonary alveoli in pneumonia and tuber- 

 culosis and in the bronchial secretion, also in the corpus luteum of the ovary, 

 the cortex of the adrenal and the retrogressive metamorphosis of the thymus 

 gland. 



Myelin was never demonstrable in the heart. It was likewise absent in fatty 

 infiltration of the liver, in the normal fat-deposits of the body, in colostrum, in 

 the secreting mammary gland and in many cases of fatty metamorphosis of the 

 kidney. j. h. p. 



c:„ 1.1 c TT u J T- , , ^T- The following conclusions are based on 



Fischler, F. Ueber den Fettgehalt von Nie- ° 



reninfarcten, zugleich ein Beitrag zur Frage a Study of the fat in kidney infarcts, 

 der Fettdegeneration. Virchow's Archiv, ^^j^j^ ^^,g^g produced experimentally in 

 170: 1 00-15 1, 1902. ^ ^ -' 



rabbits. 



The appearance of visible fat in cells, as well in the so-called fatty degener- 

 ation as in fatty infiltration, is dependent not alone upon a certain condition of 

 the cell, but also upon factors external to the cell. 



