PREFACE. XI 



has endeavoured to touch upon most of the interesting 

 subjects for microscopic observation as fully as the restric- 

 tions of a limited space, and the nature of a succinct 

 summary, would permit. To have dwelt upon each in 

 complete detail would have necessitated volume upon 

 volume, expensive books must have resulted, and this 

 would have entirely frustrated the aim which the writer 

 had in view ; he has, therefore, contented himself with the 

 humble, but, he trusts, not useless, task of setting up 

 a finger-post, so to say, to direct the inquirer into the 

 wider road. In the section of the work devoted to the 

 minuter po-riion of creation, he has ventured to dwell 

 somewhat longer here, in the belief that that department 

 is more especially the province of the microscopist. He 

 has arranged his topics under special headings, and in 

 separate chapters, for the sake of perspicuity and precision ; 

 and has brought the ever-welcome aid of illustrations to 

 convey his explanatory remarks more vividly to the minds 

 of his readers. He is peculiarly indebted to Professor 

 Quekett, whose valuable lectures, delivered annually in 

 the Royal College of Surgeons, and other multifarious and 

 successful researches, have pre-eminently distinguished him 

 as the microscopist of the day. From notes made during 

 the lectures spoken of, and from the many admirable 

 papers which this gentleman has published, much sound 

 information has been gleaned ; and the author has to thank 

 him, in the most sincere and cordial manner, for placing 

 at his disposal the mass of contributions with which he 

 has enriched microscopical science. A free use has beeu 

 made of the researches of scientific investigators generally 

 Leeuwenhoek, Ehrenberg, Carpenter, Johnston, Ralfs, 

 Busk, Gosse, Hassell, Lobb, and other members of 

 the Microscopical Society of London. His acknowledg- 

 ments are likewise due to Mr. George Pearson, for the 



