Anomalous Endosperm Development in Maize and tlip Prolilem of Bud Sports. 251 



change was from red to purple. It seems very unlikely that the change 

 could have been from white to red on one side and from red or white 

 to purple on the other side, for this would have necessitated at least 

 two distinct mutations in the same seed. The simplest possibility on 

 this assumption would be the production first of an R or of a C factor 

 in a cell lacking it, followed by the production of a P factor in a de- 

 scendant of that cell. While, for instance, a cell Crp might possibly 

 change to CRp and some of the latter's descendants change to CRP, 

 it seems very unlikely, considering the rarity of these anomalous seeds, 

 that two separate mutations would occur in the same seed. Moreover, 

 if two such mutations had occurred sometime after the endosperm had 

 begun to develop, instead of a purjjle-red seed, there would have resulted 

 a tri-color — purple-red- white — seed. 



A case of anomalous maize endosperm reported by Collins (2) is 

 of interest here notwithstanding that it can be interpreted by any of 

 the four hypotheses under consideration, provided certain assumptions 

 are allowable'). The seed was produced by the pollination of the 

 Chinese variety having waxy endosperm and colored aleurone with 

 pollen from the Gracillima variety having horny endosperm and colorless 

 aleurone. Of the crossed ear Collins says: 



The aleurone color of the Chinese variety is almost comple- 

 tely recessive to the white of the Gracillima variety with which 

 it was here crossed, and the majority of the seeds were without 

 color. The remainder showed aleurone color in spots of varying 

 size. With the exception of the single seed in question all the 

 seeds were horny, waxy endosperm being recessive to all other 

 forms of endosperm. In this one seed there was a small, waxy 

 area directly beneath a spot of aleurone color and corresponding 

 to it in shape. The coincidence of the boundries of the colored 

 spot and waxy area are so exact that the idea of the super- 

 position being the result of chance cannot be entertained. 

 Not all the genetic factors possibly concerned in this case can be 

 determined from Collins' statement. It is, however, evident that the 

 colored, waxy parent must liave had at least aleurone factors C and R 



') Collins described two anomalous seeds, but since one of tliem was borne 

 by an Fj plant tliat must have produced not less than eight sorts of gametes, it would 

 be useless to guess what genetic factors were carried by the nuclei from which the 

 endosperm developed. This seed therefore has no value for tlie purpose of this paper 

 any more than for the purpose for which it was described. 



