PREVIOUS INTERPRETATIONS OF CNIDARIA 149 



bisexual in the species Boloceroides hermaphroditicus^ as in the 

 garden -snail ; their centre is the testis, and the periphery- 

 is the ovary. ''Stephanoscyphus racemosus'' (Komai) is a scypho- 

 zoan which we consider as a primitive one and which is, 

 according to Komai (1935) still hermaphroditic in its polyp 

 generation. In its medusa generation (Nausithoe)^ however, 

 we can observe a division of sexes. The same is true for 

 the whole group Ephyropsidia where during strobilation the 

 sex cells of only one of the two types of sex cells enter 

 the Anlage of ephyrae by migrating from the basis of 

 taeniolae (sarcosepta). During the retrogression or even the 

 complete loss of the polyp generation, gonochorism becomes 

 prevalent and as a consequence of this the Lucernariidae 

 which have secondarily developed into purely sessile animals 

 become monoecious. 



On the other hand, we can again find some hermaphroditic 

 species among the generally gonochoristic Hydrozoa, e.g. 

 among the extremely retrogressed and secondarily solitary 

 Hydra. The hermaphroditic state is quite rare among Hydrozoa 

 (e.g. in the medusoid generation oi Bleutheria which, however, 

 has become "degenerated" so that it has been changed into 

 an animal that lives on the sea bottom (Fig. 26). 



As for the structure of gonads (the word "gland" instead 

 of "gonad" is not suitable for the gonads of the lowest 

 Eumetazoa; gonads can contain gland cells yet they do not 

 always have them; as a rule they are built of sex cells which 

 after all are not gland cells) we can observe, in agreement 

 with our thesis, that it is in the Anthozoa, which have evolved 

 as the first (the word "lowermost" would not be suitable 

 here) group of Cnidaria from the Turbellaria, that the gonads 

 are compact and that they possess at least a few auxiliary 

 devices; to be more precise this is true for the primarily 

 soHtary Actiniaria only. There occasionally appear follicular 

 forms with traces of spermoducts which are produced by 

 their testes; their oocytes show a type of feeding device which 

 was correctly interpreted by F. Pax (1924:787) as a remnant 

 11 



