132 EXPERIMENT STATION RECORD. 



those of the green striped plants with golden j)laiUs and also the crosses of green 

 striped plants with yellowish-white individuals which turn green, have all re- 

 snllod in first generation plants whicli wore of the normal green color. Although 

 it was impossible to note the second generation plants, except during the first 

 five weeks of their growth, it was possible at that time to identify segregates 

 of the respective categories. The results secured in these crosses, however, 

 add further evidence to the hypothesis that more than one factor is concerned 

 in the production of normal green color in the leaves of maize. Apparently 

 there is lacking in each parent some genetic factor (or factors perhaps) which 

 is concerned in the development of chlorophyll, and, since the Fi plants are 

 normal green, it appears as if that factor which is lacking in one parent may 

 be present in the other. 



" In the pure white plants no plastids could be differentiated. In the 

 yollowish-white ])lants which later may become green plastids apparently are 

 present from the first, althougli they are few in number and are verj^ small, 

 gradually increasing in number and size as the leaf turns green. 



" In 7j. japonica the manner of distribution of plastids may be compared with 

 the condition which Trelease has described in certain variegated agaves. He 

 found that the normal green condition was due to the presence of plastids 

 in the subepidermal region of the leaf. In variegated loaves, if the sti'ipe 

 was pale greenish, there was found to be a suppression of plastids through sev- 

 eral of the subepidermal cells, while in a pure white stripe there was 'all but 

 complete suppression of recognizable plastids.' " 



Perjugate cotton hybrids, C. G. Marshall (Jour. Heredity, 6 {1915), No. 2, 

 pp. 57-6 Jf, figs. 5). — This article notes the great diversity of characters that 

 appeared in the per.iugate, or second generation, while the Individuals of the 

 conjugate, or first generation, resulting from a cross between Hindi and 

 Egyptian cotton were very uniform and showed characters intermediate between 

 the two parents. 



It is noted that " studies of the different parts of the several plants, such 

 as the leaves, involucral bracts, bolls and seeds, revealed ns great diversity 

 and range of differences among these more detailed characters as there was in 

 the general appearance and habit of growth of the plants. . . , The leaves of 

 the different plants varied in color from a light or yellowish green to a very 

 dark green, some of the plants showing a bronze or reddish tinge. They also 

 varied in shape from simple leaves to leaves with deeply cut lobes, with margins 

 wavy or crenate in many dilTevcnt degrees. There was the same variation in 

 the glossy or hairy surfaces, as well as in texture and veining; in fact, the 

 leaves of sister plants were often so different that they might well have repre- 

 sented as many distinct types of cotton. . . . 



"The extra floral nectaries, which are one of the specialized features of the 

 cotton plant, also showed many aberrations and sometimes marked degenera- 

 tion. The general tendency seemed to be toward a smaller development of 

 nectaries than in the parent stocks. On the ma.iority of the plants the nectaries 

 both of the leaves and involucres were very small and inactive or altogether 

 absent. . . . 



" The bolls of these perjugate h.vbrids were perhaps more striking in their 

 diversity and possession of strange characters tlian any other parts of the 

 plant. There were many shapes, some very unusual and freakish. The bolls 

 of one plant were very long and narrow, almost cigar-shaped. Another plant 

 had bolls almost round but with a beak as long as, and in many cases longer 

 than, the body of the boll. Still another ])lant had small bolls with blunt ends 

 and a constriction at the middle which made them look like peanuts. Some 

 plants had large bolls and some small, some had bolls dotted with numerous oil 



