THE NEW GENEALOGICAL TREE 371 



use the already existing name of Parazoa Sollas 1884. It will 

 be better for us to accept the view that each taxon should 

 include one animal group only which had evolved monophyle- 

 tically; we should no longer use as a taxon the notion and the 

 name Metazoa, which should represent from now on a 

 morphological notion only. Instead of the Metazoa we should 

 rather use the name Eumetazoa when we speak of a special 

 taxon. 



The name Enantiozoa which was proposed by Delage is not 

 only younger, it is also less fortunate ; the question is not that 

 in Spongiae the three body layers occur perhaps in an inverted 

 sequence, i.e. that the skin is found in the interior of their 

 bodies and that the intestine occurs externally, but rather that 

 the Spongiae possess an external body layer which is not 

 homologous with the skin of the Eumetazoa, and a non- 

 uniform inner body layer which cannot be considered as 

 homologous to a reversed intestinal layer. These are in reality 

 morphological units which cannot be mutually compared, 

 w^hich are not mutually homologous. It is true that during 

 the ontogeny we could get an impression as if a reversion of 

 the two layers had taken place. Nothing can help here even 

 if we try to save the old interpretation by printing pictures of 

 spongulae, as has frequently been done, with the actual posteri- 

 or end (posterior as seen when the animal swims, and quite 

 generally during the polarization) turned upwards. This serves 

 as a good example of how even the most difficult problems 

 can easily be solved by means of a deliberate misrepresentation 

 of facts in false pictures. This can lead, naturally enough, to 

 apparent solutions only. 



The name Porifera, which was introduced by R. E. Grant is 

 also very characteristic of Spongiae. Now^here else in the whole 

 animal world (with perhaps the only exception of the Echino- 

 dermata) can pores be found which do not serve as openings 

 through which the animal excretes its own products or the 

 water that had been used for breathing, but rather as openings 

 which serve for the intake of water that brings the necessary 



