SKKIAL SECTION MOUNTING. 125 



Methods for Watery Sections. 



193. Foi/s Gelatin (FoL, Lehrb., p. 132). Four grammes 

 of gelatin are dissolved in 20 c.c. of glacial acetic acid by 

 heating on a water-bath and agitation. To 5 c.c. of the 

 solution add 70 c.c. of 70 per cent, alcohol and 1 to 2 c.c. of 

 5 per cent, aqueous solution of chrome-alum. Pour the mix- 

 ture on to the slide and allow it to dry. In a few hours the 

 gelatin passes into the insoluble state. It retains, however, 

 the property of swelling and becoming somewhat sticky in 

 presence of water. The slide may then be immersed in 

 water containing the sections ; these can be slid into their 

 places, and the whole lifted out; the sections will be found 

 to be fixed. 



This method is specially intended for sections made under 

 water, large celloidin sections amongst others. 



Similarly, RUPPRICHT, loc. cit., last , with the needless com- 

 plication of a seriation on Strasser's collodionised paper. 



STBASSER (loc. cit., last ) also employs a dry gelatin film 

 which he makes sticky by means of carbol-xylol. 



Methods for Celloidin Sections. 



194. The Albumen Method. I find that celloidin sections 

 may be mounted on Mayer's albumen, and have the celloidin 

 removed, if desired, by putting them into ether-alcohol. 

 Care must be taken to press them down very thoroughly 

 on to the albumen ; and it is well not to have them too wet. 



Similarily JORDAN (Zeit. u-iss. Mik. } xv, 1898, p. 54), and 

 ARGUTINSKY, ibid, xvii, 1900, p. 37. See also JORDAN (ibid., 

 192-194); DANTSCHAKOFF, Hid., xxv, 1908, p. 35; MAX mow, 

 ibid., xxvi, 1909, p. 184; ANITSCHKOW, ibid., xxvii, 1910, 

 p. 68 ; WEBER, ibid., xxix, 1912, p. 186 ; RUBASCHKIN, Anat. 

 Anz., xxxi, 1907, p. 30. Weber paints over the series on 

 the albumen with a layer of thin collodion, and puts into 

 alcohol of 50 per cent., then into a mixture of equal parts of 

 chloroform and absolute alcohol. After staining, pure 

 absolute alcohol must be avoided. 



195. SUMMERS' Ether Method (Amer. Mon. Mic. Journ.,1887, 

 p. 73). Place the sections in 95 per cent, alcohol for a 



