and future Prospects. 5485 



and confining one's views to this, which we might be forced to do were 

 they palaeontological subjects, they might be, and would have been, de- 

 clared to be of the same species : so with the zebra, the quagga, &c. 

 Now look at the exterior, and say where is the possibility of mistake. 

 But it may be said, this idea of resemblance of the interior and dissem- 

 blance of the exterior would not enable you to decide the question as 

 to the identity of the nature of both. No science of mere observation 

 is equal to this ; the profoundest zoologist that ever lived could not, by 

 any a priori reasoning, have foretold that by the union of the horse 

 and ass we should have a mule, partaking somewhat of the nature of 

 each parent, and that this mule should be barren. It is experiment 

 alone which decides such questions, not Science. The probability is 

 that the product of the ass and quagga, or zebra, of the zebra and the 

 horse, of' the zebra and quagga, would, in like manner, prove a barren 

 mule ; but nothing of all this is certain until tried. Zoology, or the 

 doctrine oflife, must not be mistaken for a fixed Science. 



Continuous production is the characteristic of species, but resem- 

 blance of the product to its parents must also be superadded. The 

 domestic dog differs in almost every country ; it has been assumed 

 that all the so-called varieties are reproductive with each other, and 

 are consequently of one species. These assumptions are hasty 

 and gratuitous ; the same has been said, on no better grounds, of 

 sheep, oxen, horses and men. Continuous production is easily 

 asserted, difficult to disprove. Since the grand era of Cuvier, natu- 

 ralists have been anxious to maintain for their favourite pursuits the 

 elevated position bestowed on them by one who worthily contested 

 precedence with the foremost of scientific men. But the Cuvierian era 

 is past and determined, — its position fixed in the history of Science ; 

 it admitted of few abstractions, — it rejected the transcendental, the 

 transformations of the embryo, and even, in some measure, limited 

 and restrained and defined the powers of Nature : these mistakes are 

 now seen and admitted. Let us proceed. 



The dog and the wolf reproduce with each other to the third gene- 

 ration, but no further ; they are then of different species : had it 

 been otherwise the world would have been harassed with a dog-wolf, 

 to distinguish which from the pure would have puzzled Linne himself. 

 The dog and jackal reproduce to the fourth generation ; " but the dog 

 and fox never have any offspring when united: they are then of 

 different genera. 1 ' It would seem, then, that in zoological Science all 

 is experiment and observation. The hyena and dog are in the same 

 category; they belong to different genera, if this test be accepted as 

 certain and real. But a very few years ago mankind was assured by 

 the most distinguished of living zoologists that the idea of species 

 was fast disappearing from human thoughts; now we are told that 

 species are the only beings in nature — that they constitute the 

 primitive forms ! Why, then, have the young generic forms? Why 

 have some of them forms which belong to the past or extinct world ? 

 Why do individuals grow up to the adult condition, occasionally with 

 forms not constantly found in their species, nor genus, uor even class, 



