4.2 ]\]r. W. Wcdckincl on AUemalion of 



my o]jiiiion, (not provided with wings and) not dioecious. 

 Tliis ancestral form must rather liave been represented by 

 somewhat worm-like creature?, which (just as, indeed, many 

 worms still do) reproduced themselves asexually and gave 

 lise polyphyletically to the different orders. From these, too, 

 there then very early branched off a portion, which likewise 

 again, precisely because it precociously developed the con- 

 dition of separate sexes, also remained stationary at tlie lowest 

 slage; while the remainder, again in consequence of longer 

 retention of the asexual mode of reproduction, had time to 

 undergo further phyletic improvement^ and only at the con- 

 clusion of their variousorthogenies also became parthenogenetic 

 or dioecious as the case may be. Here also the phylo.^eny of 

 varying length is then reflected again in a reduced or 

 "compute" metamorphosis, while the latter itself represents 

 no more than the " welding together " of the two primitive 

 generations. 



It appears exactly as though the transition to sexual repro- 

 duction is also universally connected with a pause in the 

 orthogeny, so that, if the latter takes place rai)idly or 

 ])iematurely, the whole of the rest of the organization also 

 generally remains stationary at a lower stage, while the slower 

 attainment of sexuality in the phylogeny likewise allows time 

 for a higher orthogeny. The one condition directly entails 

 the other, and 1 v.'ould term this phenomenon shortly the law 

 of jjvecucity {premaiuriii/). A more rapid ontogeny, a direct 

 development, consequently only shows that the earliest stages 

 of the asexual ancestors were already abandoned at a very 

 early period, but not that they had been altogether wanting; 

 and it may also very well be that traces of them are still to 

 be discovered even at the present time. 



Naturally my theory is not ca])able of direct proof, any 

 more than is the opposite view. I think, however, that my 

 theory is simpler and more natural, since by means of it, 

 indeed, we at cnce get rid of the entire cwuogeny, and need 

 only imagine the ontogeny as having been accelerated, but 

 not as having subsequently been altered, by side influences. 



In this way also we should surely find less difficulty in 

 ui;dersfanding the manifold transitions, which still frequently 

 occur especially between alternation of generations and meta- 

 morphosis, and with regard to which we may be in much 

 doubt as to whether we are still confionted with a reduced 

 alternation of generations or have before us an alreadv 

 commencing metamorphosis. They are all just gradations 

 of one and tlie same phenomenon, which pass without a 

 break one into the other, and with which hitherto the majority 



