188 EVOLUTION IN BIOLOGY F 
4 
new organism by the process of generation takes 
place, not suddenly, by simultaneous accretion of 
rudiments of all, or of the most important, of the 
organs of the adult ; nor by sudden metamorphosis 
of a formative substance into a miniature of th 
whole, which subsequently grows ; but by epigenesé 
or successive differentiation of a relatively homo- 
geneous rudiment into the parts and structures 
which are characteristic of the adult. 
‘‘Et primo, quidem, quoniam per epigenesin sive partiu 
superexorientium additamentum pullum fabricari certum est 
quenam pars ante alias omnes exstruatur, et quid de illa ejusqu 
generandi modo observandum veniat, dispiciemus. Ratum san 
est et in ovo manifesté apparet quod Aristoteles de perfectorum 
animalium generatione enuntiat: nimirum, non omnes pa 
simul fieri, sed ordine aliam post aliam ; primtunque existe? 
particulam genitalem, cujus virtute postea (tanquam ex principio 
quodam) reliqu omnes partes prosiliant. Qualem in plantarul 
seminibus (fabis, puta, aut glandibus) gemmam sive apicem pr 2 
tuberantem cernimus, totius future arboris principium.  Esig 
hee particula velut filius emancipatus seorsumque collocatus, 
principium per se vivens ; unde postea membrorum ordo 
itur ; cb quecungue ad absolvendum animal pertinent, dispo D 
untur.' Quoniam enim nulla pars se ipsam generat ; sed post 
quam generata est, se ipsam jam auget ; ideo eam primim orite 
necesse est, que principium augendi contineat (sive enim planta 
sive animal est, eque omnibus inest quod vim habcat vegetan di = 
sive nutriendi),? simulque reliquas omnes partes suo quamquc 
ordine distinguat et formet; proindeque in eadem primogenit: 
particula anima primario inest, sensus, motusque, et tatius vita: 
auctor et principium.” (Exercitatio 51.) 
1 De Gencratione Animaliwm, lib. ii. cap. x. 
2 De Generatione, lib. li. cap. iv. 
[se ae eae, 
PI cme Ws, ot, 
Sa ONT eT Uae eve Ts VT RMPN! ere RW ETOP EY wt UPAR ITT MRT | Ty 
