Descendenz und Hybriden. — Morphologie und Teratologie. 389 



„Each of these pairs is inherited independently of the 

 others, so that all kinds of combinations appear among the 

 off spring." 



„The first two pairs of iinit characters, short and Angora 

 coat, normality and albinism, have been fully investigated, and 

 in their heredity are found to follow Mendel's originales«/« 

 type in regard to dominance, segregation and gametic purity." 



„The investigation of the two remaining pairs of characters, 

 grey and biack coat, self-colour and Dutch markings, is not 

 yet completed. So far as the experiments go however the 

 following results appear: 



Grey and black coat. — Black is recessive to grey in 

 the first generation, segregates in Mendelian proportions in the 

 second generation , and breeds true in the third generation, 

 notwithstanding its grey ancestry." 



„in regard to the greys an interesting complication was 

 observed. The original grey used was a pure yellow-grey, 

 containing more yellow pigment and less black than the ordi- 

 nary wild grey. The greys of the first, second, and third ge- 

 nerations were all wild greys, and, so far, there has been no 

 return to the original pure yellow-grey," 



„Seif colour and Dutch markings. — So far as the 

 experiments go, these characters appear to be neither dominant 

 nor recessive to one another, but give variable intermediate 

 marked hybrids in the first generation. Segregation into the 

 three forms in Mendelian proportions, however, takes place in 

 the second generation, and, so far, the extracted self-coloured 

 and Dutch-marked forms have bred true in the third generation, 

 while the intermediate marked hybrids give the three forms 

 again in accordance with the Mendelian principles." 



The factors for grey and for black coat, and for self-colour 

 and for Dutch-markings exist in the albinos though in an in- 

 visible state, and, in albino matings, these factors appear to 

 follow the ordinary Mendelian rules of segregation and of ga- 

 metic purity. 



„These results confirm and extend to rabbits, results already 

 obtained by Prof. Cuenot in mice, though it would appear 

 that the heredity of Dutch markings in rabbits differs in some 

 respects from that of the „panachure" in mice." R. H. Lock. 



PUNNETT, R. C, Mendel ism. (Cambridge, Macmillan and Bowes. 

 12 mo. 1905. 63 pp.) 



A populär general account of Mendelian and post-Mendelian 

 discoveries. Mendel's life is touched upon and the earlyneglect 

 of his work alluded to. A description follows of Mendel's 

 experiments with peas. Among experiments subsequent to 

 Mendel's own, examples of crosses between different strains 

 of rabbits, fowls, and mice among animals, and of sweet peas, 

 and maize among plants are briefly described, together with 

 the economically interesting case of immunity to rust in wheat. 



