340 



Journal of Agricultural Research vou xxii, no. ? 



the spelt. The curve of these gradations is not a binomial frequency 

 curve, but, on the contrary, more individuals are found, as a rule, at the 

 extremities of the range than near the center. This fact may be ob- 

 served in Table I, which shows the forms of the Fj segregates. 



Table I. — Number of plants of the F^ generation falling into each of lo classes, based on 

 presence or absence of spelt characters, with total number of spelts arid wheats actually 

 obtained, calculated numbers on basis of j to i ratio, deviation, probable error, and ratio 

 between deviation and probable error 



Series. 



Crosses. 



Number falling in class — 



To- 

 tal. 



13255a 



13260a 



13263a 

 3094a 



3085a 



13124a 



13125a 



Spelt sel. i344oXDale Gloria set. 



13401 



Spelt sel. 13438 X Turkey (C. I. 

 3375) sel. 13389 



Dale Gloria sel. i340iXspelt 



Black Bearded spelt X Early Red 

 Chief 



Black Bearded spelt X Jones Long- 

 berry 



Vulgare (C. I. 3338)Xspelt sel. 



13437 



Crimean (C. I. 3340) sel. 13351X 

 spelt sel. 13437 



63 



25 



81 



50 

 76 



5° 



Total of crosses . 



418 



Series. 



13255a 

 13260a 

 13263a 

 3049a 

 3085a 

 13124a 

 13125a 



Crosses. 



Spelt sel. i344oXDale 



Gloria sel. 13401 



Spelt sel. 13438 XTurkey 



(C.I- 3375) sel. 13389- 

 Dale Gloria sel. 13401X 



spelt 



Black Bearded spelt X 



Early Red Chief 



Black Bearded spelt X 



Jones Longbcrry 



Vulgare (C. I. 3338) X 



spelt sel. 13437 



Crimean (C. I. 3340) sel. 



i335iXspeltsel. 13437 



Total of crosses . . . 



Number of plants. 



Obtained. 



Spelts. Wheats. 



52 

 49 

 18 



52 

 37 

 56 

 41 



305 



113 



Calctilated. 



Spelts. Wheats. 



54-8 



47-3 

 18.8 

 60.8 



37-5 

 57- o 

 37-5 



313-5 



IS- 7 

 6.2 

 20.3 

 12.5 

 19. o 

 12.5 



104.5 



Devia- 

 tion. 



8.5 



Prob- 

 able 

 error. 



2-5 

 2-3 



1-4 

 2.6 

 2. I 



2.5 

 2. I 



6.0 



Ratio 



Dev . 

 P.B. 



•74 

 •57 



3-38 

 .24 

 .40 



I. 67 



I. 42 



As it is impossible to distinguish the homozygous spelts from the 

 heterozygous forms, in determining the ratios all the spelt and speltoid 

 forms (classes i to 9) have been grouped together and compared with 



