Reviews and Book lYo/ices. 1 1 5 



specimens produced may be said to conform with the theories 

 of Mendel, who teaches that the characters of the germ-celis 

 do not fuse with others but merely ming-le, and that the pairing- 

 of two similar aberrant specimens of this character would result 

 in the production not of a brood precisely similar to their 

 parents, but of one, in which only half the offspring- would 

 resemble their imniediate progenitors, and of these indi^•iduals 

 thus externally resembling their parents, only a moiety (or 

 25 per cent, of the total number of young) are really purely 

 sinistral, capable of breeding true ; the remainder inheriting- 

 and transmitting a latent tendency to dextrorsity. 



Similarly, of the dextral progeny of the sinistral parents, 

 half will be purely dextral forms with power to produce onl}' 

 dextral offspring-, whereas the other moiety, though also dex- 

 trally coiled, possesses a latent sinistral tendency, and their 

 descendants would be composed of sinistral and dextral in- 

 dividuals in the same ratios of 25 per cent purely dextral 

 specimens, 25 per cent purely sinistral, and 50 per cent of 

 individuals combining the tendency to dextral and sinistral 

 modes of convolution, the underlying- principle being- that 

 although a particular individual may not display the special 

 character in question, yet the peculiarity may still be possessed 

 by its germ-cells, and will be transmitted to, and re-appear in 

 the progeny. 



It is to be hoped that further precise observations may be 

 made on these most interesting points. 



Last Words on Evolution : A Popular Retrospect and Summary. 

 By Ernst Haeckel. Translated by J. McCabe. A. Owen & Co. 1906. 

 127 pages, 6/-. 



In this volume Mr. McCabe has earned the gratitude oj English 

 natin-alists not familiar with the German language, by enabling them to 

 read for themselves Haeckel's matured views on the evolution problem, 

 as put forward in his now famous Berlin lectures of 1905. It will be 

 remembered that recently it was announced that Professor Haeckel had 

 abandoned Darwinism and given public support to the teaching of a Jesuit 

 writer. This was subsequently contradicted, but the result was a desire on 

 the part of the educated English public to know more of Haeckel's precise 

 attitude in this matter. The present volume contains the ' three famous 

 lectures delivered at Berlin,' which 'are the last public deliverance the aged 

 professor will ever make.' The chapters are (i) 'The Controversy about 

 Creation, Evolution and Dogma," (2) 'The Struggle over our Genealogical 

 Tree, our Ape relatives and the \'ertebrate Stem," (3) ' The Controversy 

 over the Soul, the Ideas of Immortality and God.' As an appendix there 

 are some useful ' Evolutionary Tables.' Amongst the plates is an excellent 

 portrait of Haeckel. The book is well produced. 



1906 April I. 



