Lect. IV.J THE STRUGGLE FOR LIFE. 93 



ages, have had a talent to occupy with ; this taleut, so 

 to speak, was the innate inherited morphological force. 



As to ascent in the scale of vertebrate life, some have 

 made their one talent ten, others two ; those, however, 

 which did not improve themselves, even in the midst of 

 untoward surroundings, had to pass into the darkness of 

 extinction. Even such a type as the Lamprey shows a 

 great stride beyond the form whose imago is still seen 

 in the temporary Ammocoete (Sand-pride, or larval 

 Lamprey). 



The Singing-Bird had, probably, at one time, an 

 ancestor but few removes from an Ammocoete. But 

 the former comes of an ambitious stock ; and now, in the 

 end of the world, whilst the home of the Lamprey is 

 still in the sand and the mud, the surroundings of the 

 Bi]"d are the trees, and the sky, and the laughing sun- 

 shine. 



Myriads of types, unready and conservative, have 

 passed out of being ; that which they had, but did not 

 improve, has been taken from them, whilst others, by 

 steady improvement of what they had, have had more 

 and more life given to them. But not always by slow, 

 steady increment "during long ages" has the advance 

 l)een made. Nature does, now and then, make amazing 

 leaps, certain types taking on sudden metamorphosis, 

 and, in the fraction of a life time, the low is transformed 

 into the high. 



These beautiful creatures — the Edentata — have l^een 



