The Microscope. 369 



sometimes of half of the diameter of the fibre from which it is 

 given ofp. The remaining portion, aa was said, continues like an 

 ordinary tapering end of the branching variety. This branching 

 tapering end is applied to the surface of a full- sized fibre, as are the 

 tapering ends described above. I was unable to determine the 

 connections of the thick branch. Like the endings of the first class, 

 there was always more or less connective tissue adhering to its end 

 and sides. Where the striated and unstriated fibres join, the former 

 terminate in an unbranched, tapering end that is surrounded by 

 unstriated muscle cells joined to it by means of cell cement. 

 (Bib. 6.) 



METHODS. 



To soften and remove the connective tissue so that the muscle 

 fibres could be easily separated, three methods were employed: 



1. Boiling in water. 



2. Macerating in 20 per cent, nitric acid. The oesophagus 

 should be filled with the acid and the ends tied, then suspended in a 

 long jar of the same liquid. It is necessary to allow it to remain 

 thus from six hours to three days, depending upon the temperature. 



3. Heating in 5 to 10 per cent, nitric acid (HNO3). This 

 method is used when it is desired to study the specimen at once. 



The first method was useful only in the gross anatomy, and 

 even in this case was not as satisfactory as the methods following. 

 Boiling enough to make the fibres easily separable sometimes renders 

 them friable. If the second or third method is used, the material 

 must be perfectly fresh, for it is found that otherwise the muscular 

 fibres will soften before the connective tissue. After treatment with 

 nitric acid the muscle was found to continue to soften if kept in 

 water or alcohol. Prof. Gage found that this softening could be 

 prevented by keeping the tissue in a saturated aqueous solution of 

 alum. Befoi'e the immersion in alum-water, the fibres cannot be 

 satisfactorily stained, but after remaining in this solution for a few 

 hours, hsematoxylon stains them excellently. 



BIBLIOGRAPHY. 



1. Allen, Harrison, 1884, — A System of Human Anatomy. 

 Philadelphia, p. 641. 



2. Blasius, Gerardus, 1681. — Anatome Animalium. Amster- 

 dam. 



3. Chauveau, A, 1873: — The Comparative Anatomy of the 

 Domestic Animals. 2nd ed., translated by George Fleming. New 

 York. p. 379. 



