PBEFACE. 



THAT the thorough study of concrete animal types is a 

 necessary preliminary to good work in Zoology or Comparative 

 Anatomy will now be granted by all competent judges. At a 

 time when these subjects, though much lectured upon, were 

 rarely taught, Dollinger, of Wiirzburg, found out the right 

 way. He took young students, often singly, and made them 

 master such animal types as came to hand, thereby teaching 

 them how to work for themselves, and fixing in their minds a 

 nucleus of real knowledge, around which more might crystallise. 

 " What do you want lectures for ? Bring any animal and 

 dissect it here," said he to Baer, then a young doctor longing 

 to work at Comparative Anatomy.* It was Dollinger who 

 trained Purkinje, Pander, Baer, and Agassiz, and such fame 

 cannot be heightened by words of praise. In our own time and 

 country Bellinger's methods have been practised by Professor 

 Huxley, whose descriptive guides, such as the Elementary 

 Biology and the delightful little book on the Crayfish, now 

 make it easy for every teacher to work on the same lines. 

 From the description of the Cockroach in Huxley's Anatomy 

 of Invertebrated Animals came the impulse which has 

 encouraged us to treat that type at length. It may easily 

 turn out that in adding some facts and a great many words to 

 his account, we have diluted what was valuable for its 

 concentration. But there are students those, namely, who 

 intend to give serious attention to Entomology who will find 

 our explanations deficient rather than excessive in detail. It 

 is our belief and hope that naturalists will some day recoil from 

 their extravagant love of words and names, and turn to 



* Baer's account of Dollinger is to be found in the Leben und Schriften von K. E. 

 von Baer, 8. 



