.3^. SOME NEW BOOKS. 543 



expect the same typical structures to be always present within the 

 limits of the same type ; and, as this is not the case, the hind limbs 

 being absent, for instance, in the whales, the assumption of the 

 creationist must be abandoned. But this is obviously a iion seqnitiir. 

 It would be equally true to say that the absence of hind limbs in the 

 whale proves that the animal does not belong to the vertebrate 

 phylum. 



Even if we consider the facts of embryology, which are the most 

 striking evidence of the truth of evolution, it is not possible to show 

 that they are absolutely incompatible with the creation doctrine. 

 The creationist may say, if he pleases, that when man was created 

 it was ordained that he should pass through iish-like stages in his 

 embryological development, so that the ideal unity of the vertebrate 

 phylum might be more perfectly maintained. It is impossible to 

 disprove such an assumption. The logical reply to the creation 

 hypothesis is that it assumes a multitude of miraculous occurrences 

 for which there is absolutely no room in Nature, so far as we know 

 it by human observation and reasoning ; while at the same time the 

 hypothesis as upheld by naturalists in Darwin's time, including a 

 succession of creative epochs, could lay no claim to support from 

 supernatural revelation. 



Mr. Romanes' restatement of the argument for evolution is divided 

 into five chapters, containing the evidences from Classification, Mor- 

 phology, Embryology, Palaeontology and Geographical Distribution 

 respectively. Of these, the chapter on Embryology is by far the worst, 

 being unfortunately crowded with errors and inaccuracies. The first 

 case described of the persistence of ancestral organs in the embryo, is 

 that of the external gills of the foetus of the Alpine Salamander. This 

 case is mentioned by Darwin on the somewhat unsafe authority of 

 G. H. Lewes, who wrote that the gills of the foetus had no reference to 

 the future life of the animal, nor any adaptation to its embryonic condi- 

 tion, that they had sole reference to ancestral adaptations, and repeated 

 a phase in the development of its progenitors. Mr. Romanes still 

 supposes that this is a correct account of the matter, although it must 

 be evident to anyone who has studied Fraiilein von Chauvin's paper 

 on the subject that the foetal branchiae have been specialised and 

 enlarged for the purpose of intra-uterine respiration. It is true that 

 the foetal branchiae are capable of aquatic respiration outside the body 

 of the mother, but it is also true, although not mentioned by Mr. 

 Romanes, that the great size and delicacy of these branchiae were 

 the actual cause of death to all the larvae with which Fraiilein von 

 Chauvin experimented except one, and that one escaped the fate of 

 its brethren only by getting rid of its uterine gills and growing new 

 ones of more serviceable size and character. 



A large number of pages are next devoted to a detailed discussion 

 of the relations of the Metazoa to the Protozoa, a discussion which 

 it is very difficult to criticise. It is certainly interesting, but it also 

 certainly belongs in many respects to the post-Darwinian, not the 

 Darwinian period. The discussion is difficult to follow, and I fear 

 will not be thoroughly intelligible to the general reader who is des- 

 titute of even the most elementary knowledge of Natural Science, 

 for it requires some acquaintance with Weismann's theories to under- 

 stand the author's meaning. He says, for instance, that not only 

 the individual development but klso the powers of asexual repro- 

 duction on the part of multicellular organisms are all ultimately due 

 to the specialised character of their germ-cells. He points to the 

 karyokinesis of the segmenting ovum and the formation of the polar 



