DISTINCTIVK (MIAHAC'TERR OF IIINM)! J'LANTS. 17 



quite tlitl'erent from the Hindi bracts, in jspite of endless variations 

 in the minor details. 



The calyx of the Hindi cotton has five distinctly prominent 

 trianiiular lobes, one or two of which are often produced into a 

 narrow needle-like point. Tii the Eir;\^ptian cotton the lobes of the 

 calyx are very short and broadly rounded, never produced into long 

 points. Three examples of the toothed cah'x of the Hindi cotton 

 are shown in Plate III; an Egyptian calyx and the calyx of a hybrid 

 in riate IV. 



The fresh, newly opened flowers of the Plindi cotton have pale 

 creamy-white petals like those of l^pland cotton instead of lemon- 

 yellow petals like Egyptian cotton. In the afternoon the flowers 

 of both sorts change to a reddish pink, but the Hindi flowers attain 

 a much deeper shade than the Egyptian. 



The petals of the Hindi cotton are shorter than those of the 

 Eg\'ptian and open more widely. The Hindi flower may be de- 

 scribed as cup-shaped, the Egyptian as tubular. 



The purple s]K)t found at the base of each petal in Egyptian 

 flowers is lacking or only faintl}' indicated in typical Hindi flowers, 

 though often quite pronounced in Hindi hybrids. 



The pollen of the Hindi cotton is of a much paler yellow and the 

 individual pollen grains are much smaller than those of the Egyptian 

 cotton. 



FRUIT CHARACTERS OF HINDI COTTON. 



The bolls of the Hindi cotton have a rounded conic shape, broadest 

 near the base, and taper abruptly to a short point. Egyptian bolls 

 are more fusiform, narrower at the base than near the middle, and 

 taper less abrupth' to a rather blunt apex. The shape diflfers appre- 

 ciably with the conditions, the less luxuriant plants in Egj^pt having 

 a bi-oader and more conic form than is usual in Arizona, more like 

 the bolls produced bv the Egyptian cotton in the vicinity of Los 

 Angeles. (See PI. VI.) 



The surface of the Hindi bolls has a rather dull pale pea-green 

 color, with only slight indications of the deeply buried oil glands. 

 Egyptian bolls, on the contrary, have a fresher, darker color, with 

 the surface smooth and shining, but rather deeply pitted around the 

 numerous superficial oil glands, each of which appears as a distinct 

 black dot. These differences appear somewhat less pronounced in 

 Egypt than in Arizona. Pale-green bolls were found on many 

 plants that seemed in all other respects to represent true Egyptian 

 cotton. The darker color of the bolls in Arizona may be connected 

 with the greater luxuriance of the plants. 



The number of carpels, or " locks," varies in the Hindi cotton from 

 3 to 5, the majority of bolls having 4 locks. In the Egyptian cotton 



210 



