SUMMARY 275 



and function; and the resemblance of the homologous 

 parts or organs in allied though distinct species, though 

 fitted in the adult state for habits as different as is 

 possible. Larvse are active embryos, which have been 

 specially modified in a greater or less degree in relation 

 to their habits of life, with their modifications inherited 

 at a corresponding early age. On these same principles — 

 and bearing in mind that when organs are reduced in 

 size, either from disuse or through natural selection, it 

 will generally be at that period of life when the being 

 has to provide for its own wants, and bearing in mind 

 how strong is the force of inheritance — the occurrence of 

 rudimentary organs might even have been anticipated. 

 The importance of embryological characters and of rudi- 

 mentary organs in classification is intelligible, on the 

 view that a natural arrangement must be genealogical. 

 Finally, the several classes of facts which have been 

 considered in this chapter seem to me to proclaim so 

 plainly, that the innumerable species, genera and families, 

 with which this world is peopled, are all descended, each 

 within its own class or group, from common parents, and 

 have all been modified in the course of descent, that 

 I should without hesitation adopt this view, even if it 

 were unsupported by other facts or arguments. 



