TKANSMUTABLE. 223 



persicaria* T. cruda* H. dysodea, P. ineticulosa* 

 H. chenopodii* H. marginata,* E. cratcegata* 

 0. Udentata,* E. angularia, A. letularia* C. 

 pusaria* F. conspicuata, E. linariata* E. cen- 

 tauriata,* E. Haworthiata, E. satyr ata, E. deno- 

 tata, E. nanata* E. subnotata, E. almnthiata* 

 E. assimilata* E. coronata* E. solrinata. 



Then we are told of a group of forms, such as 

 these caterpillars, which, in the majority of in- 

 stances, hardly move at all, except to and from 

 their food, that the ''embryos are active." Mr. 

 Darwin takes this assumed difference between 

 the larva and imago, as one proof that they 

 diifer also in structure, and that they are 

 adapted for special uses of life. He also alludes 

 to the resemblance of embryonic existence lasting 

 till a rather late age. He cannot either see 

 why the looped condition of the arteries near 

 the branchial slits, should exist equally in the 

 young mammal, the egg of the bird, or the 

 spawn of the frog; and then, again, he makes 

 a comparison of an equal difficulty, existing in 

 a similarity of the bones in the hand of man, 

 the wing of the bat, and the fin of the porpoise. 

 If, however, Mr. Darwin had not been blinded 

 by his theory, he would have seen at once that 

 the embryos he has mentioned, have to live an 

 aquatic existence before birth. Why, therefore, 

 should not the arrangement in these branchiae be 

 on the same type, as that which is found to 

 answer so admirably in the gills of the fish? 



After some more writing, Mr. Darwin asks, 



