and future Prospects. 5407 



jackal. Finally, this mongrel (the eighth of a jackal) with a female 

 dog; the product has nothing of the jackal in it — it is a dog."* It 

 seems that, if the female jackal had been employed instead of the 

 female dog, the last product would have been a jackal. 



We confess that we do not see in such an experiment a refutation of 

 the doctrine of the pre-existence of germs : the product reverted to 

 the species which prevailed ; but whether the germ pre-exist or not, it 

 produces a being with generic forms, and these must have a meaning, 

 a signification, it being admitted by all that the productive energy is 

 limited to analogous species and genera. Buffon knew some of these 

 facts, nevertheless he thought it right to offer another system of the 

 origin of beings — the system of organic molecules. Voltaire alone 

 could handle such systems ; he struck them with a word, and they fell, 

 like the card-constructed houses of children. Life is the most obscure 

 of all mysteries : its results are beings with structures infinitely com- 

 plex : in the analysis of these beings by observation and dissection 

 we arrive at certain facts, of which the latest discovered are incom- 

 parably the most wonderful : they reveal to us the extraordinary and 

 almost incredible fact that the embryos of all animals resemble each 

 other ; that, in the progress of the young from the ovum upwards, they 

 assume forms belonging to other species and genera; that the young- 

 bird has branchia or gills, as well as lungs — the young fish, lungs as 

 well as gills ; that man himself is not exempt from these metamor- 

 phoses, which seem regulated by laws as constant and uniform as the 

 specialization of the adult — metamorphoses and transformations as 

 curious as those imagined by Ovid, and far more true. Any system 

 or theory which takes not such facts into account is sure to be 

 unsatisfactory and at fault, if not entirely untrue; they cannot, in fact, 

 be any longer overlooked. 



When we consider these facts of embryogeny, combining them 

 w r ith the obvious scale or chain of the animal creation, from the most 

 simple to the most complex, running, as it were, in parallel lines, 

 the reflection deepens, even though we may question that other view 

 (successive creation) superadded to it in modern times by Paleontology, 

 and which seems in course of being refuted. Nevertheless there are 

 many respectable paleontologists, if we may so say, who still hold by 

 the theory, for want, we presume, of a better — that animals have been 

 formed and succeeded each other on this globe, in an order pro- 

 ceeding from the more simple to the more complex, repeating, as it 

 were, the embryonic forms and metamorphoses, as well as the existing 

 chain of beings. These facts, it is true, are not systems nor even 

 theories, but they are the materials out of which future theories must 

 be formed. The philosophy of Zoology must assume a character in 

 unison with the precise mechanical, mathematical and experimental 

 philosophy of the day. The era of ingenious conjecture is passed 

 as regards human physiology and anatomy — it closed with the advent 

 of the illustrious Bichat; as regards Chemistry, with Davy ; Hutton 



* Fleurens. 

 XV. X 



