44 Dr. F. von Warner on 



fci' 



Goette * expresses himself in a precisely similar fashion : — 

 " Since the first Ephyra-clisk is only the further developed 

 oral segment of the Scyphostoma, it naturally follows that it 

 can in no way be regarded as a bud. That which reminds 

 us of gemmation in it, e. g. the outgrowth of the circlet of 

 lobes, belongs, just as does the previous outgrowth of the 

 tentacles of the Scyphostoma — both of which processes are 

 indeed termed ' sprouting ' (' Hervorknospen ') in looser 

 phraseology — simply to the progressing development of the 

 entire segment, which preserves its identity. It follows that 

 the liberation of the first Ephyra can also be nothing else 

 than the separation of two segments of an organism, both of 

 which are in process of development, but were already in 

 existence before — or, in other words, simple fission. On the 

 abandoned peduncle of the monodiscous larvae, however, the 

 new Ephyra arises in precisely the same way as the first, by 

 a transformation of what is originally its oral section into tlie 

 disk of a Scyphostoma, whicli develops only secondarily into 

 the disk of an Ephyra. For the formation of Ephyraj in 

 the case of the monodiscous larvaj gemmation is therefore 

 entirely out of the question. But owing to the agreement of 

 this process in the case of the mono- and polydiscous larvae 

 this necessarily applies to the latter just as much as to the 

 former. The disk of the Ephyra therefore never arises by 

 gemmation, and thus strobilation is in all cases a simple 

 fission of larvas in process of development." 



With regard to the phenomena which immediately succeed 

 the actual separation of the Ephyra from the Scyphostoma, 

 both in the case of the liberated Ephyra-Medusa as also in 

 that of the Polype which is left behind, Goette f remarks that 

 " therein is repeated merely a process of regeneration analo- 

 gous to that in the development of any other organism with 

 terminal mouth — be it a Worm, Infusorian, or anything else 

 — whereby the general import of the previous or simultaneous 

 process of fission is in no way prejudiced. It is likewise 

 clear that in this respect the regeneration of the proboscis can 

 be of no greater account than that at the gaping crown of 

 the previously liberated Ephyra : both phenomena are inevit- 

 able accompaniments of fission, which the development of 

 the first and all subsequent Ephyrge of a polydiscous Strobila 

 cannot exhibit in materially different guise." 



"With reference to the supposed instances of gemmation 



* A. Goette, ' EntwicMungsgeschichte der Aurelia aurita und Cotylo- 

 rhiza tuberctdata,' Leipzig, 1887, p. 50. 

 t Op. cit. p. 46. 



