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scriber of Nature, is rendered comprehensible only by the confident style as well as by the neatness of his diagnoses, by which, with a single stroke, he put an end to the indefinite character of Natural History, and appeared to contemporaries and posterity as a lawgiver. The exaltation of species as the basis of all systematic comprehension had never been so explicitly proclaimed. His opinions culminate in the maxim," "Reason teaches that at the beginning of things; a pair of each particular species was created." But with Linnæus this said reason looks rather strange, for it is subservient to the strictest Scriptural belief, and he endeavours to harmonize his geological conceptions with this standpoint.
One very effective geological phenomenon was especially striking to him, namely, the upheaval of a great portion of the Scandinavian coast. It proceeds more rapidly than the subsidence of another part; its phenomena are far mightier; and thus the idea might be formed that the continent had risen from the sea in regular progression. "I believe that I am not straying far from the truth," he says, "if I affirm that in the infancy of the world all the mainland was submerged and covered by an enormous ocean, save one single island in this immeasurable sea, on which all animals dwelt and plants grew luxuriantly.”
It follows that all species of plants likewise existed in this lovely garden, as it is expressly said that Adam named every animal; consequently all insects must have been assembled in Paradise, but insects cannot be imagined without plants. Linnæus then makes the first attempt at animal geography by making the animals disperse themselves from this centre. But the summary
of his idea of species is invariably, "We reckon as many species as the Infinite Being created at the beginning."10 And his authority was so powerful that the age of Voltaire and of Diderot devoutly accepted this obvious dogma, and transmitted it to posterity as a maxim impossible to question.
Linnæus was, however, so little of an anatomist that in this province Zoology required a completely fresh foundation, and, in the capacity of a second Linnæus, Cuvier stood forth." His school styles itself the school of facts, yet it was by no means without a tincture of philosophy. On the contrary, the definite and simple nature of his principles and deductions could not fail to be imposing. He epitomized the summary of his observations as "Laws of Organization;" and he applied the teleological view, the principe des causes finales, with great advantage to the knowledge and restoration of antediluvian animals. The question of the persistency or mutability of species thrust itself forcibly upon him. For this an external cause was given by the Egyptian expedition and the investigation of mummified animals. Etienne Geoffroy St. Hilaire and Lamarck attacked the persistency of species, and held that, especially considering the stability of external conditions, the Egyptian period was far too short for the identity of the mummies with the species now extant, to make it possible to infer the immutability of species; but the question was curtly despatched and silenced by the predominating school of Cuvier.
Meanwhile, Cuvier not only increased the accumulation of facts, but, as we have already hinted, he grouped them so happily and with such philosophical
skill that he undoubtedly approached the object at which he aimed-the Natural System. He supplied the first reliable information respecting extinct species. With regard to those which had replaced them in subsequent periods, he was not, as is generally supposed, an unqualified partizan of new creations, but he refrained from any fixed opinion. "I will not," he says,' "positively affirm that for the production of the present animals a new creation was required. I merely say they did not live in the same locality, and must have come from elsewhere." Geoffroy Saint Hilaire, on the contrary, does not doubt that the animals now living are descended, by an unbroken succession of generations, from the extinct races of the antediluvian age.
Cuvier's method involved the danger of introducing dogmatism into natural science, and it is therefore justifiable to refer in this place to one of Cuvier's immediate disciples only recently deceased-Louis Agassiz, who in the most rigidly didactic manner adheres to the systematic categories, and invests them with fine-sounding definitions as "embodied creative ideas." According to him, species belong to a particular period in the world's history, and bear definite relations to the physical conditions predominant at the time, as well as to the contemporaneous plants and animals. Species are founded on well-defined relations of individuals to one another and the world in which they live, as well as on the proportions and mutual relations of their parts, and on their ornamentation.
Individuals, as representatives of species, bear the closest relations to one another; they exhibit definite relations also to the surrounding element, and their
existence is limited within a definite period. Of genera
We may pronounce these definitions to be mere phrases, and inquire with Haeckel: "Of what nature are these 'ultimate structural peculiarities of some of their parts' which are supposed alone to define the genus as such, and to be exclusively characteristic of each genus? We ask every systematizer whether he may not equally well apply this definition to species, varieties, &c., and whether it is not finally the ultimate structural peculiarities of some of their parts' which produce the characteristic forms of the species, the variety, &c. In vain do we search in the "Essay on Classification" for a single example of the manner in which, for instance, the genera of oxen or antelopes, the races of hyænas and dogs, or the two great genera of our fresh-water bivalve shells, the Unio and Anodonta, are actually distinguished by "the ultimate structural peculiarities of some of their parts." Several of these definitions given by Agassiz may be interchanged point-blank, so general and merely negative are their statements. He characterizes the classes "by the manner in which the plan of the type is executed as far as ways and means are concerned." The orders, "by the degree of complication of the structure of the types.'
These phrases are interchangeable, but, like all dogma. tism, they make a great impression on those who from ignorance of the facts are incapable of criticising for themselves, and they are readily quoted to confute an unbelieving investigation of nature by one made in faith.
It might be thought that if the affair were so simple, and systematic ideas so firmly fixed, nothing would be easier than to establish the system. And so Agassiz maintains. He says that if a single species of any of the great animal groups were present, and admitted of investigation, the character of the type, class, family, genus, and species, might be determined. The weakness of this and similar statements may best be demonstrated by examining the basis of all dogmatic system, -the "species." If this idea be mutable, if the species be not given once for all, but variable, according to time and circumstances, the implications of the higher and more general ideas of genus, family, &c., must necessarily ensue. The keenest and most logical criticism on the deeply-rooted scholastic idea of "species" was made by Haeckel,20 after Darwin, in his classical work on the "Origin of Species," had completely exposed the old doctrine and practice of zoology and botany. In what follows we shall adhere to Haeckel.
We have seen above that Linnæus accepted the Creation as an irrevocable scriptural doctrine, and it is really absurd that many naturalists who have long abandoned any other dogma, should abide by this one. Therefore as the Bible mentions the creation of species, this legend was made the basis of all science. It is true there are not now many who appeal to scriptural testimony.