127 



II. EXPERIMENTS IN HYBRIDIZING OR CROSSING VARIETIES. 111. 

 EXPERIMENTS IN PRESERVING SPORTS OR VARIATIONS. 



These two methods of improvement may as well be considered to- 

 gether, for in the present condition of the sorghum plant it is hard to 

 draw the line between them. The different varieties which have be- 

 come established cross so readily with one another that where variations 

 occur, in a field of cane for instance, it is often difficult to say positively 

 whether it is a true sport, whether it is from one seed of a distinct va- 

 riety accidentally introduced, or whether it is from a seed that had 

 been cross-fertilized from a different variety. Doubtless both causes 

 of variation obtain to a large extent, for the one is a natural consequence 

 of the other; that is, on account of the readiness with which two in- 

 dividuals cross, a large number of vaiietics have been produced, and as 

 many of these are not well established or fixed they exhibit a constant 

 tendency to revert to original types, thus showing variations. Whether 

 the wide variations shown in the different kinds of sorghum are due 

 more to crossing or more to type variation, is a question it is unneces- 

 sary to discuss here. It is sufficient to show that such capability for 

 variation does exist. In the work done at this station no distinction 

 could be made between variations produced by crossing and those which 

 were true sports. As this season's work was only the beginning it was 

 impossible to obtain true artificially-produced crosses j that is, varia- 

 tions produced by the careful cross-fertilization of two distinct and 

 definite types. The plots called " crosses " were planted from seed- 

 heads obtained by Mr. Deuton from various fields of sorghum, and were 

 simply variations from the general type of the cane growing about 

 them. In the great majority of cases the canes produced from this 

 seed showed such well-marked reversions to two well-defined types 

 that it was a pretty fair presumption that they actually did result from 

 the cross-fertilization of those types. But of course such work should, 

 in the future, be carried out upon known types artificially cross fertil- 

 ized. 



GENERAL OBSERVATIONS ON CROSSES. 



Kol renter says, "Ho who would produce new varieties should cross 

 varieties." 



Darwin says: "In regard to the beneficial effect of crosses between 

 varieties there is plenty of evidence." "The crossing of two forms 

 ;vhich have long been cultivated implies that new characters actually 

 arise, some of which may be valuable and permanent." "It would be 

 superfluous to quote more, for Gartner, Herbert, Sagcret, Lecoq, Nau- 

 din, and many other eminent experimenters speak of the wonderful 

 vigor, size, tenacity of life, precocity, and hardiness of hybrid produc- 

 tions." 



It is stated in the Sugar Beet* that "if a superior variety of beets bo 

 placed near another variety, the result will be most advantageous, and 



* The Sn-:ir Mrrt, by Lewis E. Ware. 



