THE STUDY OF STRUCTURE. 329 



CHAPTEK IX. 



The Study of Structure. 



the morphological question and its pro- 

 gressive answers. 



One of the naturalist's first questions — ^however 

 learnedly he may phrase it^is just one of the child's 

 first questions, asked long before it can speak — 

 " What is this ? '' In how many different tones — of 

 fear, of awe, of wonder, of inquisitiveness — has this 

 question been asked since man and science began! 

 Was it not Aristotle's question when a new specimen 

 was brought to him ? was it not the question on the 

 Challenger, when the dredge came up ? is it not the 

 question on the lips of every teacher and student of 

 natural history to-day? — What is this? It is a 

 " simple question," but how hard to answer, as we 

 press it further and further home, from external 

 features to internal structure, from organs to tissues, 

 from tissues to cells, as we put one lens after another 

 in front of our own, as we call to our aid all sorts of 

 devices — scalpel and forceps, razor and microtome, 

 fixative and stain. " What is this," we say, " in 

 itself and in all its parts ? what is this by itself and 

 when compared with its fellows and kindred ? " and 

 our answer broadens and deepens till it furnishes the 

 raw materials of the science of Morphology. 



The answer to the question : What is this f asked 



