PREFACE. 



THE first Edition of Professor VAN DER HOEVEN'S manual 

 was published in parts between the years 1827 and 1835. 

 He undertook the labour, as he informs us, not with any 

 desire to add one more to the numerous works with a 

 similar title already in existence, which should be neither 

 better nor worse than these. On the contrary, if he had 

 found any one of them to be a sufficient guide for his 

 public teaching, without great alterations, he would have 

 abstained from his contemplated task. Accordingly, the 

 plan of his work differed from that of most other manuals 

 in beginning with the simpler forms of animals, and pro- 

 ceeding upwards to the highest : and from that of all of 

 them, in embodying a much larger amount of anatomical 

 information. His work was received with marked appro- 

 bation not confined to the limits of his own country. 

 During the lapse of nineteen years, which intervened 

 between the first and second editions, the acquisitions 

 both of Zoology and Zootomy had been greatly enlarged, 

 so that in many departments the former science had 

 assumed an entirely new aspect. Consequently the second 



