304 6. Vererbungslehre. 



la meme combinaison, d'hybrides vrais et de faux hybrides qui, dans six cas, 

 sont du type maternel et dans un cas, du type paternel. 



C. L. Gatin (Paris). 



838) Tower, W. L., The Determination ofDominance and the Modi- 

 fication of Behavior in Alternation (Mendelian) Inheritance 

 by Conditions Surrounding or Inciclent upon the Germ Cells at 

 Fertilization. A Correction and Addendum. 



(Biol. Bull. 20,1. p. 67-69. 1 fig. 1910.) 

 In this paper the author notes in the previous paper of the same title 

 (Biol. Bull. 18,6. 1910) the data and plate of a wrong experiment were intro- 

 duced into the printer's copy in place of the experiment intended for the Po- 

 sition and indicated by the remainder of the paper. The necessary corrections 

 are supplied here, and this note should therefore be consulted in connection 

 with the previous paper. Lillie (Chicago). 



839) Gager, St. C. (Brookly Botanic Garden), Cryptomeric inheritance 

 in onagra. 



(New York Academy of Science, Section of Biology. Jan. 16. 1911.) 



Beference was made to an abnormal plant of Onagra biennis that 

 appeared in a pedigreed culture following exposure to radium rays of the 

 ovule employed in producing the plant. The plant possessed two primary 

 shoot-systems (rosettes and subsequent cauline stems) of equivalent value, but 

 manifesting entirely unlike morphological characters. Photographs were shown, 

 and various possibilities were suggested as to the cause or causes of the 

 anomaly. That the effect was due to the exposure to radium rays was held 

 to be possible, though not conclusively shown. The anteceedent history of the 

 plant, and the fact that hybrids between the two unlike halves manifested, in 

 the Fj and F 2 generations, the characters of only one of the parent shoots, 

 was interpreted to emphasize the fact, already recognized, that the inheritance 

 of a character and its expression are two quite different phenomena. 



Hussakoff (New York). 



840) BuilSOW, R., Inheritance in Bace-horses: Coat-colour. 



(Mendel. Journal 2. p. 74—93. 2 pedigree charts. 1911.) 

 The author refers to previous work which indicates that bay colour is 

 dominant over chestnut. A number of apparent exceptions to this occur in 

 the Stud Book, in which two chestnut parents are stated to have had bay 

 foals. Several of these are examined, and it is shown that the Statement is 

 due to error, owing to the difficulty of determining the colour in a young foal. 

 The grey colour is then dealt with, and it is shown that this is domi- 

 nant to bay or brown. Evidence is given that when homozygous it is nearly 

 white, whith black mane, tail and feet. Heterozygous greys on the other band 

 may be brown when foals and become grey later. Cases are also given of 

 foals which were born grey and became brown. Doncaster (Cambridge). 



841) Russo, A., A reply to a note of W. E. Castle entitled „Busso 

 on sex-determination and artificial modification of the Mende- 

 lian ratios. 



(Biologisches Zentralblatt 31,1. p. 29—32. 1911.) 



842) Russo, A., Über den verschiedenen Metabolismus der Kaninchen- 

 eier und über ihren Wert für das Geschlechtsproblem. 



(Biologisches Zentralblatt 31,2. p. 51—58. 1911.) 

 Der Verf. weist die von Castle und Punnet geübte Kritik seiner Unter- 



