Mr Compton, On Bight- and Left-Handedness in Barley. 503 



IV. The question as to a possible regularity in the arrange- 

 ment on the parent plant of seeds bearing definite characters is 

 of great interest. Prof. Bateson considers that there is a strong 

 a priori presumption that some regularity exists : but as he and 

 Miss Killby were unable to discover any such regularity in Peas, 

 he is "disposed to think that the process of oogenesis in which 

 the dominant or recessive character of the egg-cell is determined 

 must be liable to disturbance by accidents*." 



In the present case it appeared probable that some such 

 arrangement might be discovered ; though, as will be shown later, 

 there is here no evidence of heredity. But the character under 

 consideration is one of symmetry, and is determined early in 

 embryogeny ; and it seemed not unreasonable to expect that the 

 symmetry of the parent spike might have some clear influence 

 over the symmetry of the embryos borne upon it. 



The attempt to discover such an order of arraugement of the 

 right- and left-handed offspring on the parent ear gave, however, 

 inconclusive results. Table III shows the aggregate numbers for 

 the odd and even rows of seeds on the spike. It will be seen 



T ■p 



that the ratio — ^— ^ in seeds from odd rows is slightly higher than 



in those from even rows. The total difference is 1'53%. This 

 discrepancy might be considered insignificant, were it not that 

 the accuracy of the counts, as judged by the agreement between 

 the two classes of spikes, appears to be very high. The fact that 

 both classes of spikes gave a difference between odds and evens 

 in the same direction is also slightly in favour of regarding this 

 difference as significant. 



Clearly, however, the evidence is inconclusive ; and it would 

 be rash to try to found upon it any theory of the influence of the 

 position of the seed on the parent on the character of the seedling 

 developing therefrom. 



No more significant result was obtained by a study of indi- 

 vidual spikes. Many single ears of " Plumage Corn," " Kinver 

 Chevalier " and " Goldthorpe " were examined carefully with a 

 view to discovering any regularity which might exist in the 

 arrangement of the seedlings borne upon them. No such regu- 

 larity was discernible, however. 



In a paper by Mackloskief the following statement is made: 

 " The grains arising on adjoining rows in the ear of corn [maize] 

 are of different castes, and produce ' antidromic ' plants (that is, 

 growing up in opposing curves), and that the same property 

 belongs to all the Gramineae." So remarkable is this assertion in 

 the light of the above results for barley, that I repeated Mack- 

 loskie's experiment on maize ; but completely failed to confirm 



* Reports to the Evolution Committee of the Royal Society, ii. 1905, p. 69. 

 t " Antidromy in Plants," Amer. Naturalist, xxix. 1895, p. 973. 



