IHIS. 



105 



hybrid ami /. trojana curve* are practically absolutely 



the name and above tin- /. \lur\-, i i ur\r in the leactioni 



ith sodium italic) il with the parental 



i-ur\i-- in tin- reurtiuii with (Kitnvmim PII||P|HH yainr 



iir-: .livniii lute and then the highe.-' rev in the 



rekiiti.'h- with .-'.mini 1. . although there are but 



littledillerciuf-i ; and th- uul then intermediate in 



tin- r. .t. : ...:i- with j>..M--;uin i.~!i.|.-. tending to be close to 



the < urxe of I. lr,ij,ina. The In lin.l nine i lower than the 



tal .ime* in tin- i with potassium hydrox- 



i|>rn i hloride, cobalt uitrato, luinuni chloride, aiid 



chloride. although the < ..halt-nitrate and 



barium-chloride curve* are very little different from tin- 



nil . ur\r; and the highest throughout the 60 



minute* in the uranium-nitrate reaction. 



(4) In very few reaction* ia there a marked period 

 of early resistance followed by a comparatively rapid 

 x' latiiu.atii.il. A hru-f jn-riod of early resistance of all 

 i!ir. e starches is suggested by the curves of the strontium- 

 nitru f one or the other parent or the 



hybrid in the reactions with chloral hydrate, chromic 

 .uin nitrate, uranium nitrate, and copper ni- 

 trate, especially in the last 



Tli<' earliest period during the 60 minute* at 

 which the three curves are beat separated to differentiate 

 i h< -Mr. hes varies with the different reagents. Approxi- 

 mately. this period occurs within 5 minutes in the reac- 

 tions with pyrogallic acid, sulphuric acid, hydrochloric 

 ami, potassium iodide, potassium sulphocyanate, sodium 

 hydroxide, sodium salicylate, uranium nitrate, and cop- 

 IT nitrate; at 15 minutes with chromic acid, potassium 

 hydroxide, calcium nitrate, strontium nitrate, and cupric 

 chloride ; at the end of 30 minutes with chloral hydrate, 

 nitric acid, potassium sulphide, and sodium sulphide; 

 and at the end of 60 minutes with cobalt nitrate, barium 

 ehloride, and mercuric chloride (with the last perhaps 

 at the end of 30 to 45 minutes). 



REACTION-INTENSITIES OF THE HYBRID. 



Tlu< Mftion treats of the reaction-intensities of the 

 hybrid as regards sameness, intermediateness, excess, and 

 deficit in relation to the parents. (Table A 30 and 

 Charts D 379 to D 399.) 



The reactivities of the hybrid are the same as those 

 of the seed parent in the iodine, gentian violet, and 

 safranin reactions ; the same as those of the pollen parent 

 with potassium iodide and sodium hydroxide; the same 

 as those of both parents with potassium eulphocyanate 

 and sodium hydroxide; intermediate with temperature, 

 chloral hydrate, chromic acid, pyrogallic acid, nitri. 

 sulphuric acid, hydrochloric acid, potassium sulphide, 

 sodium sulphide, calcium nitrate, strontium nitrate, and 

 copper nitrate (in four being closer to the seed parent, 

 in two being closer to the pollen parent, and in six bem_' 

 mid-intermediate) ; the highest with uranium nitrate, 

 and nearer that of the pollen parent; and the lowest with 

 polarization, potassium hydroxide, cobalt nitrate, cupric 

 chloride, barium chloride, and men-uric chlori'l 

 three being closer to the seed parent, in one closer to the 

 pollen parent, and in two being as close to one as to 

 the other parent). 



The following is a summary of reaction-intensities : 

 Same as seed parent, 3 ; same as pollen parent, 2 ; same 

 as both parents, 2 ; intermediate, 12 ; highest, 1 ; lowest, 6. 



It seems from the foregoing data that the seed parent 

 has exercised much m-n- influence than the pollen parent 

 on the characters of the starch of the hybrid. Apart 

 from this the mott ...n- feature." are the marked 



tendency to intermcdiatencss and a ten.leiiey to lowness 

 of the hybrid. 



COMPOSITE CDIVH op KEACTION-INTEWSITIES. 



This section treats of the composite curves of the 

 reaction-intensities, showing the differentiation of the 

 starches of /ru timed, /. trojana. and /. umali. (t 'hart 



The most conspicuous features of this chart are: 



(1) The closeness of all three curves, the parental 

 .nrxe, ruiiinnj; no rl.-ely t-vtlirr aa to suggest very 

 closely related species (/. iberica ia, however, relegated 

 to Uncocyliu and /. trojana, to A pay on. well-separated 

 subgenera of the rhizoiuatous series). (The grou; 



of the Irids by different botanists are by no means the 

 same, and it is recognized as being questionable if 

 the classification of the entire genus must not be 

 reconstructed.) 



(2) The curve of /. iberica tends, with the exception 

 of the polarization and temperature reactions, to be In-low 

 that of /. trojana; but the differences are usually slight, 

 and most marked in those with iodine, gentian violet, 

 temperature, chloral hydrate, chromic and, |x>tassium 

 sulphocyanate, sodium sulphide, sodium salicylate, cal- 

 cium nitrate, uranium nitrate, copper nitrate, ciipru- 

 chloride, and mercuric chloride. 



(3) The curve of the hybrid wavers in its parental 

 relationships, sometimes being closer to one parent and 

 at others to the other, with for the most part a tendency 

 to sameness or intermediateness, occasionally above or 

 below parental extremes. 



(4) In /. iberira, the very high reactions with sul- 

 phuric acid, potassium sulphocyanate, and sodium sali- 

 cylate; the high reactions with chromic acid and sodium 

 hydroxide; the moderate reactions with polarization, 

 iodine, gentian violet, safranin, temperature, pyrogallic 

 acid, and potassium hydroxide; the low reactions with 

 chloral hydrate, nitric acid, hydrochloric acid, sodium 

 sulphide, calcium nitrate, strontium nitrate, copper ni- 

 trate, and cupric chloride; and the very low reactions 

 with |M>tasMiim sulphide, uranium nitrate, cobalt nitrate, 

 barium chloride, and mercuric chloride. 



(5) In /. trojana, the very high reactions with sul- 

 phuric acid, potassium sulphocyanate, and sodium sali- 

 cylate; the high reactions with chromic acid and sodium 

 hydroxide; the moderate reactions with polarization, io- 

 dine, gentian violet, safranin, chloral hydrate, pyrogallic 

 acid, nitric acid, hydrochloric acid, potassium hydroxide, 

 and potassium iodide; the low reactions with temperature, 

 sodium sulphide, calcium nitrate, strontium nitrate, cop- 

 per nitrate, and cupric chloride; and the very low reac- 

 tions with potassium sulphide, uranium nitrate, cobalt 

 nitrate, barium chloride, and mercuric chloride. 



(6) In the hybrid, the very hij;h reactions with sul- 

 phuric acid, potassium gulphocyanatc, and sodium salicyl- 

 ate; the high reaction* with chromic acid and sodium 

 hydroxide; the moderate reactions with polarization, io- 

 dine, gentian violet, chloral hydrate, pyrogallic acid, 

 nitric acid, potassium hydroxide, and potassium iodide; 

 the low reactions with temperature, hydrochloric acid, 

 sodium sulphide, calcium nitrate, uranium nitrate, trn 

 tium nitrate, copper nitrate, and cupric chloride ; and the 



>w reactions with potassium sulphide, cobalt nitrate, 

 barium chloride, and mercuric chloride. 



Following is a summary of the reaction-intensities : 



