VI PEEFACE. 



region, to weave a specimen chaplet, a sample coronal, 

 which may tell of the good things belilnd. Yet the se- 

 lection has been so made as to leave untouched no con- 

 siderable area of the great field of Zoology which is 

 under the control of the Microscope ; so that the stu- 

 dent who shall have verified for himself the observa- 

 tions here detailed, will be no longer a tyro in micro- 

 scopic science, and will be well prepared to extend his 

 independent researches, without any other limit than 

 that which the finite, though vast, sphere of study itself 

 presents to him. 



The staple of the work now ofi'ered to the public 

 consists of original observation. The author is far 

 trom thinking lightly of the labours of others in this 

 ample field ; but, still, it is true that, respecting very 

 many of the subjects that came under his notice, he 

 found, in endeavouring to reproduce and verify pub- 

 lished statements, so much perplexity and difficulty, 

 that he was thrown back upon himself and nature, 

 compelled to observe <f^ novo^ and to set down simply 

 what he himself could see. The ever accumulatinsr 

 stock of observed and recorded facts is the common 

 property of science ; and the author has not scrupled 

 to reproduce, to amplify, or to abridge his own obser- 

 vations which have already appeared in his published 

 works and scientific memoirs, as freely as he would 

 have cited those of any other observer, in which he 

 had confidence, and which were germane to his pur 



