X ON THE STUDY OF BIOLOGY 285 



earth-worm, a snail, a squid, and a fresh-water 

 mussel. We examine a lobster and a cray-fish, 

 and a black beetle. We go on to a common skate, 

 a cod-fish, a frog, a tortoise, a pigeon, and a rabbit, 

 and that takes us about all the time we have to 

 give. The purpose of this course is not to make 

 skilled dissectors, but to give every student a clear 

 and definite conception, by means of sense-images, 

 of the characteristic structure of each of the lead- 

 ing modifications of the animal kingdom ; and 

 that is perfectly possible, by going no further than 

 the length of that list of forms which I have 

 enumerated. If a man knows the structure of 

 the animals I have mentioned, he has a clear and 

 exact, however limited^ apprehension of the essen- 

 tial features of the organisation of all those great 

 divisions of the animal and vegetable kingdoms 

 to which the forms I have mentioned severally 

 belong. And it then becomes possible for .him 

 to read with profit ; because every time he meets 

 with the name of a structure, he has a definite 

 image in his mind of what the name means in 

 the particular creature he is reading about, and 

 therefore the reading is not mere reading. It is 

 not mere repetition of words ; but every term 

 employed in the description, we will say, of a horse, 

 or of an elephant, will call up the image of the 

 things he had seen in the rabbit, and he is able to 

 form a distinct conception of that which he has not 

 seen, as a modification of that which he has seen, 



