30 DIMORPHIC LEAVES IN RELATION TO HEREDITY. 



very possibly this particular form, as also the far-famed Dacca cotton, stands every 

 chance to have been carefully investigated in the New World. But the fact that 

 G. arboreum var. neglecta has preserved in the United States, during probably close 

 on 300 years of cultivation, identical characteristics to those it possesses under the 

 widely different environment of India, argues strongly against the structural pecul- 

 iarities by which it is recognized being viewed as merely geographical and climato- 

 logical features, that change or disappear under altered conditions. * * * 



But with reference to the survival of this presumably Indian plant in America and 

 elsewhere (after its cultivation had been abandoned), it may be observed that once 

 a particular species or race of cotton had been introduced into a favorable cotton- 

 growing country, even though its regular cultivation might chance to be discon- 

 tinued, it would be no great stretch of imagination to believe that a specially hardy 

 stock, such as the present plant, might survive for centuries. * * * The fact, 

 however, remains that G. arboreum var. neglecta has been repeatedly recorded as met 

 with in the United States of America, and in the examples seen by me the plants in 

 question could not possibly be separated botanically from the corresponding Indian 

 stocks.' 



It has not been found possible to produce hybrids between our 

 American Upland varieties and the Asiatic species, though large num- 

 bers of experiments have been made in both India and the United 

 States. In view of the failure to produce hybrids the Asiatic cottons 

 can not be considered as close relatives of the American Upland type, 

 though they show the same general range of variations of leaf forms. 

 That the close similarity of leaf form should have led Watt to refer 

 an American Upland cotton to an Asiatic species may be considered 

 as a further testimony to the complete parallelism of variation. 



Another okra-leaved variation of Upland cotton was considered by 

 Watt to represent a hybrid of Gossypium punctatum or G. Mrsutum 

 and G. schottii, the last being a new species described by Watt as a 

 wild plant in Yucatan. The idea that the narrow-leaved condition 

 could be reached as a ''natural sport" or mutative variation from a 

 broad-leaved variety like the King is tacitly rejected in the following 

 paragraph : 



G. schottii, as defined by me above, must of necessity be a wild plant, since its 

 inferior grade and low yield of wool would never justify its cultivation. It, how- 

 ever, matches sufficiently closely a hybrid found in a field of King's Improved cotton 

 at Richmond, Va. (recently sent to me by Mr. Lyster II. Dewey of the Bureau of 

 Plant Industry in the United States of America), as to countenance the belief that 

 the so-called sport in question may have originated through the hybridization of G. 

 punctatum or of G. Mrsutum with the present species. The specimen came to me 

 under the vernacular name of okra — a name that it will be recollected had on a former 

 occasion been given to an American sample of G. arboreum var. neglecta. It is sug- 

 gestive of the West Indian name ochro (Hibiscus esculentus) and possibly thus denotes 

 the deeply dissected condition of the leaves. From the remark on the attached label 

 of the jiresent specimen it may be inferred that the American authorities were 

 induced to believe that, though widely different from King's Improved, it was per- 



1 Watt, G. The Wild and Cultivated Cotton Plants of the World. 1907, pp. 81, 101, and 102. 

 221 



