34 EXPERIMENT STATION RECORD. 



the Stamens were fertile. Flowers having both ovaries and sterile stamens 

 often had less than 3 stamens. Fertile and sterile stamens were never found 

 in the same flower. Spikelets with 2 ovaries never had any fertile stamens, 

 but sometimes had from 1 to 3 sterile stamens. 



" The occurrence of a larger percentage of 2-flowered spikelets near the tip 

 of the female inflorescence may be taken to indicate that the tip of the ear 

 is less highly specialized than the remainder of the ear. That there is a well- 

 defined tendency for both male and female spikelets to become many flowered 

 is evidenced by the fact that 1 spikelet has been found with 3 seeds, and male 

 spikelets with many more than the normal number of stamens are of common 

 occurrence. The development of 2 ovaries in 1 spikelet is not definitely cor- 

 related with the abortion of the other spikelet of the pair. A few cases have 

 been found where 4 seeds have developed from the 2 spikelets of a pair and 

 many pairs that have produced 3 seeds. The development of 2 ovaries in 1 

 spikelet must be simultaneous, as a large number of cases have been found 

 where the 2 seeds fi-om 1 spikelet have grown together with a single pericarp. 

 These connate seeds had been fertilized through a double silk which was 

 attached to the pericarp near the union of the 2 seeds. Connate seeds are 

 a distinct phenomenon from single seeds with a double embryo, 2 of which have 

 been seen. 



" The development of 2-flowered female spikelets is looked upon as a reversion 

 to a more primitive type, the tendency of evolution being toward more compli- 

 cated types with more highly specialized parts. Neither Euchlaena nor Trip- 

 sacum, the 2 nearest known relatives of Z. mays, have 2-flowered female spike- 

 lets, and the occurrence of this character in maize is held to strengthen the 

 relationship between Zea and the Andropogoneae, already indicated by the 

 occurrence of androgynous flowers." 



Heredity of a maize variation, G. N. Collins (U. S. Dept. Agr., Bur. Plant 

 Indus. Bui. 272, pp. 23, pi. 1, fig. l).—ln 1909 a white ear appeared in a care- 

 fully selected yellow variety of corn under circumstances indicating that the 

 ear must have arisen as an abrupt mutative change of character. The ear was 

 fully matured and well filled; the cob, red in the original variety, was pure 

 white; and the seeds appearing pure white had in most cases a very faint 

 trace of yellow near the base. A report on the progeny of this albinistic ear 

 through the first, second, and third xenia generations is given and a study of 

 a cross of this ear with a pure white dent variety and with the Hopi variety is 

 also discussed. 



In a review of the results, the author states that in a general way the pure- 

 seed progenies of the albinistic ear resulted in all shades of yellow from the 

 merest trace to the fully developed orange of the variety from which the muta- 

 tion originated. It is pointed out that the pronounced tendency for the seeds to 

 fall into two groups representing 25 and 75 per cent of the total number shows 

 that the inheritance is Mendeloid. though not definitely alternative, and that 

 this grouping suggests that in a single character with somewhat variable domi- 

 nance is involved. The appearance in some of the ears of a class apparently 

 pure white, representing approximately 6.25 per cent, is regarded as suggesting 

 that two factors are involved but that under tUose conditions the definite class, 

 representing 25 per cent of the seed in the same ears that show the pure-white 

 class of 6.25 per cent, can not be readily explained on the factor hypothesis. 

 From a theoretical standpoint, the fact considered the more sigiaificant is that 

 while the segregation was usually numerically correct, it was by no means com- 

 plete, that is, the dominant character, yellow endosperm, was not completely 

 absent from individuals of the recessive class. 



