Apes. 215 



number Five, the Gastrcea (Urdarmthiere) a 

 class of animals purely imaginary. They are 

 placed here because required as ancestors for 

 the Gastrula, itself an imaginary order, derived 

 from embryological exigencies. 



No. 8 is another imaginary type, called by 

 Haeckel Chordonia, because they "developed 

 themselves from the Annelida, by the formation 

 of a spinal marrow and a chorda dorsalis " ! x It 

 is well known that between the Invertebrata 

 and the Vertebrata there is no transition form. 

 It is also known (by Mr. Darwin) that, by 

 means of the Ascidians, we are supposed to 

 "have at last gained a clue to the source whence 

 the Vertebrata have been derived." z But as to 

 that " group of marine animals resembling the 

 larvae of existing Ascidians," which were our 

 "most ancient progenitors in the kingdom of 

 the Vertebrata " : 8 who they were, or what, 

 or whence, is known to no one but Professor 

 Haeckel ! True, even he does not profess to 

 have any producible evidence that such animals 

 ever existed ; they are destitute of any single 

 living representative ; there is no fossil evidence 

 of their former existence ; their sole raison d'etre 



1 " Natiirliche Schopfungsgeschichte," p. 583. 

 * "Descent of Man," vol. i. p. 205. 

 Ibid. 



