10 CHAPTER I. 



make tissues that have lain in it for some time very brittle. 

 The brittleness is, however, sometimes very helpful in minute 

 dissections. Another property of clove oil is that it does not 

 easily spread itself over the surface of a slide, but has a 

 tendency to form very convex drops, and this also makes it 

 frequently a very convenient medium for making minute 

 dissections in. 



9. General Principles. For an excellent exposition of the principles 

 underlying modern histological technique, the reader may consult with 

 advantage the paper of PAUL MAYEK, in Mitth. Zool. Stat. Neapel, ii 

 (1881), p. 1, et, seq. See also the abstract in Journ. -Roy. Mic. boc. (N.S.), 



11 (1882), pp. 866881, and that in Amer. Natural., xvi (1882), pp. 697- 

 706, in which two last some improvements are mentioned which have been 

 worked out since the publication of Mayer's paper; and further, the history 

 and criticism of modern methods contained in APATHY'S MiTcrotechnik der 

 thierischen Morphologic, Braunschweig, H. Bruhn, 1896. 



