290 NATURAL SCIENCE [May 



Here is a strange confusion between classification and nomenclature, 

 between the conception and tlie mode of expression. This confusion 

 is not due to scientific men, for there can scarcely be a working 

 zoologist or botanist who has not protested that the binominal 

 system does not represent the facts of nature; nor is the system 

 universally accepted. How far the Duke is from apprehending 

 this is shown by the still more startling remarks on pp. 36, 37. 

 The following is given as a certain, undoubted, indisputable fact : 

 " All the fresh forms of life in the past were specifically constant — 

 just in the same way, and to the same degree, as existing forms 

 are specifically constant now. There was no mixture. Each new 

 pattern of creature kept its shape and pattern till it vanished. Each 

 came and went with equal suddenness. . . . Experts in the fossils 

 of each great rock-formation can discriminate all the species of a 

 contemporary and of a succeeding time from each other, with the 

 same precision and absolute identification as we can discriminate 

 living species from each other now." Now this statement is not 

 merely uncertain, doubtful and disputable, but we affirm that it is 

 absolutely untrue, and that if its illustrious author had ever spent 

 a week in the scientific study of those Cretaceous Terchratidae or 

 Liassic ammonites that he mentions with such assumption of know- 

 ledge, he would have had its untruth forced upon him. People who 

 are not experts can discriminate species with all the precision the 

 Duke of Argyll thinks necessary for his argument, but this is just 

 what the expert finds impossible — or, when it is possible, then he 

 knows that the gaps which limit species are but the expressions of 

 his own ignorance. 



We need not combat the statement that the genus Terebratula 

 "appeared in some of our oldest rocks," but it is surprising to see 

 the idea of the persistence of certain organic types brought forward 

 as though no modification of it had been rendered necessary by the 

 advance of knowledge during a quarter of a century. So too the 

 peculiarly erroneous remarks about the Lias ammonites might pass 

 as mere slips, were it not that they convey a distinctly false impres- 

 sion, and prejudice the mind of the audience. It is not true that 

 ammonites appear in the Lias for the first time, but were it true, 

 their connection with the ancestral goniatites would be none the 

 less close. It is not true that the species of ammonites are rigidly 

 confined to zones, and that there is no link between them, " no 

 uncertainty as to the minutest marks of difference and of identity." 

 This is perhaps the idea one gets from text-books and from lists of 

 fossils, but it is not the idea of the field-geologist or the practical 

 monographer of ammonites. 



To treat this kind of thing seriously is almost as absurd as the 

 Duke's own scarification of Mr E. Stenhouse, A.E.C.S., who, it seems, 



