THE COASTS OF SICILY. 37 



than that of seeing life progressively manifested 

 before his eyes in a body which had hitherto been 

 apparently inert, and of watching a seed or an egg 

 becoming transformed into a plant or an animal. The 

 development of a germ realises in its phenomena 

 of evolution the strangest metamorphoses that the 

 imagination of poets had ever conceived, and by its 

 phenomena of epigenesis we are enabled to take part 

 as it were in creations of a still more incomprehen- 

 sible character. All these mysteries, which are accom- 

 plished beneath the eye of the observer, were long 

 regarded as marvellous but isolated facts, which were 

 not investigated beyond the point necessary for their 

 confirmation. At the present day, however, we turn 

 to these facts for a solution of the highest problems 

 of natural philosophy. And here the first question 

 which presents itself is : Where are the termination 

 and commencement of the vegetable and the animal 

 kingdoms ? What are the common attributes of the 

 representatives of these two fundamental types of 

 animated creation ? What are the links that associate 

 the offspring with its progenitors, constituting that 

 ideal being which we term a species ? Deeply in- 

 teresting are questions such as these, which it is 

 perhaps reserved for embryology to answer, now that' 

 naturalists have ceased to limit their studies to a few 

 representatives of the highest types, and have ex- 

 tended their researches to the last links of the great 

 series in the scale of being. 



Among the most difficult problems that naturalists 

 have proposed to themselves for solution, there is 

 one, perhaps, which they will never definitely solve, 



D 3 



