Marshall: Perjugate Cotton Hybrids 



61 



discover any general correlations or 

 definite associations between any of 

 the more important stnictural differ- 

 ences. 



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 different degrees. There was 

 the same variation in the gloss}' or hairy 

 surfaces, as well as in texture and vein- 

 ing; in fact the leaves of sister plants 

 were often so different that they might 

 well have represented as many distinct 

 types of cotton. 



Figure 4 gives an idea of some of the 

 differences and peculiar characteristics 

 of the involucral bracts of five of the 

 perjugate hybrid plants. The bracts 

 not only differed in size, shape, texture 

 and coloring, but many of them revealed 

 in their position around the boll new 

 traits entirely foreign to either of the 

 parent stocks. In one case the bracts 

 performed a peculiar twist at the ends, 

 leaving the boll exposed and giving the 

 appearance of a toy pin wheel, especially 

 if viewed from above. The bracts of 

 another plant were very large and con- 

 cave or inflated, completely enclosing 

 the bolls. 



DIFFERENCES IN BOLLS AND SEEDS. 



The extra-floral nectaries, which are 

 one of the specialized features of the 

 cotton plant, also showed many aber- 

 rations, and sometimes marked degen- 

 eration. The general tendency seemed 

 to be toward a smaller development of 

 nectaries than in the parent stocks. 

 On the majority of the plants the nec- 

 taries both of the leaves and involucres 

 were very small and inactive or alto- 

 gether absent. One plant, however, 

 had very large and active nectaries, 

 larger than is customary with either of 

 the parent stocks. Another plant had 

 one active nectary on the midrib of the 

 leaf and the nectaries inside the in- 

 volucral bracts were large and active, 

 but those on the outside of the in- 

 volucral bracts were inactive, and 

 often lacking altogether. 



The bolls of these perjugate hybrids 

 were perhaps more striking in their 

 diversity and possession of strange 

 characters than 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 

 plant 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 glands and some with few, some 

 plants had bolls deeply pitted and some 

 had bolls with smooth surfaces, the 

 oil glands being more deeply buried in 

 the tissues of the wall. 



The seed and lint characters were as 

 diverse as the boll characters. The 

 seeds from the different plants were of 

 many sizes and shapes and no two 

 plants showed the same distribution of 

 fuzz on the seed. The seed of one 

 hybrid plant was entirely naked while 

 usually there were tufts of fuzz at either 

 the apex or base of the seed or at both 

 ends, these tufts varying in size for the 

 different plants. Several plants had 

 the seeds completely covered with 

 thick fuzz, but even these differed from 

 each other in that some had green fuzz, 

 some brown and some pure white. The 

 lint also varied greatly in both quantity 

 and quality and ranged in color from 

 a pure white to a decided buff. From a 

 commercial standpoint the lint would 

 have been of little value because of the 

 variation in length and quality of the 

 lint from the different plants. 



A few descriptions of individual 

 Hindi-Egyptian hybrid plants of the 

 perjugate generation may help to show 

 how diverse they were, and how in 

 many cases their characters ranged be- 

 yond either of the parent stocks. The 

 plants here described were grown from 

 self -fertilized seed of one conjugate 

 Hindi x Egyptian plant. The first six 

 plants were grown from seed of one 

 boll, the next three from another boll 

 and the last three from a third boll. 

 No attempt is made to cover all the 



