NEW INTERPRETATION OF CNIDARIA 305 



the primitive Infusoria. Rajkov asserts that even now species 

 can be found among the lower Infusoria which do not have 

 a "nuclear dualism." As an example he mentions Stephanopogon 

 Lwoff (1936) whose body has several equal nuclei which are 

 not polyploid and which contain only little DNA. Quite 

 bizarre is the case of Trachelocerca phoenicoptera (Rajkov) with 

 its complex karyon which develops by way of a union of 

 several macronuclei and which also encloses six micronuclei. 

 This sounds very strange and it can be interpreted only as a 

 lateral development from the main line that evolution had 

 taken in connection with conditions that are typical of the 

 higher Infusoria. In the conjugant of the same species we 

 find a larger number of the so-called pronuclei (gamocyte 

 karyons) from seven to twenty-two. They develop into 

 three to six androgametic karyons (migrating nuclei). 

 The fertilization is multiple, its result, however, is one zygote 

 only w^hich remains alive while all the rest is lost. Rajkov is 

 right when he concludes that this is a remnant of a former 

 multiple formation of gametes and that the conjugation of 

 the Infusoria had therefore evolved from such sexual condi- 

 tions that are characterized by the gametogenesis and by 

 the copulation, a fact which several years ago I did not only 

 maintain but also tried to prove (Hadzi, 1950). 



Trachelocerca belongs to the holotrichous Holophryidae which 

 Rajkov believes to be the most primitive Infusoria. We can 

 expect that many interesting facts will still come to light du- 

 ring the future researches. 



The Origin of the Complex 

 Hypercellular Individualities 



We will now return to the problem of the cellularization 

 w^hich was so thoroughly discussed by Hanson. All 

 biologists agree that the monocellular state with one cell 

 nucleus, thus the primary independent monokaryon, represents 



