CALANTHE. 



137 



high reactions with polarization and safranin ; and the 

 moderate reactions with iodine, gentian violet, tem- 

 perature, pyrogallic acid, nitric acid, and potassium 

 hydroxide. 



Following is a summary of the reaction-intensities: 



40. COMPARISONS OF THE STARCHES OF CALANTHE 

 VESTITA VAK. RUBRO-OCULATA, C. REGNIEEI, AND 



C. BRYAN. 



In the histologic characteristics, polariscopic figures, 

 reactions with selenite, qualitative reactions with iodine, 

 and qualitative reactions with the various chemical rea- 

 gents the starches of parents and hybrid exhibit proper- 

 ties in common in varying degrees of development and 

 in each case more or less marked individualities. The 

 hybrid C. bryan is in form in the majority of the grains 

 closer to C. regnieri, and in a minority of the grains 

 closer to C. vestita var. rubro-oculata. In hilum and 

 lamellae it is closer to C. regnieri. In mean size the 

 grains are larger than those of either parent but closer 

 to C. regnieri, while in proportion of length to width 

 they are closer to the other parent. In polariscopic figure 

 and reactions with selenite it is closer to C. regnieri. 

 In the qualitative reactions with iodine it is closer to 

 C. regnieri. In the qualitative changes during heat 

 gelatinization it is, during the first stages, closer to C. 

 regnieri, but during the later stages closer to the other 

 parent. In the qualitative reactions with chloral hydrate, 

 chromic acid, nitric acid, and sodium salicylate it is closer 

 to C. vestita var. rubro-oculata, but in those with hydro- 

 chloric acid and sodium salicylate it is closer to C. 

 rignieri. 



Reaction-intensities Expressed lit/ I. if/lit, Color, am! Tempera- 

 ture Reactions. 

 Polarization: 



C. vest. v. rubro-oc., moderate to very high, value 70. 

 C. regnieri, very low to very high, much lower than in C. vestita 



var. rubro-oculata, value 35. 

 C. bryan, very low to very high, intermediate between the parents, 



value 45. 

 Iodine: 



C. vest. v. mbro-oc., moderate, value 50. 



C. regnieri, moderately light, lighter than in C. vestita var. rubro- 

 oculata, value 35. 



C. bryan, moderate, intermediate between the parents, value 38. 

 Gentian violet: 



C. vest. v. rubro-oc., moderate to deep, value 60. 



C. regnieri, light to moderately deep, lighter than in C. vestita var. 



rubro-oculata, value 50. 

 C. bryan, moderate to moderately deep, intermediate between 



parents, value 53. 

 Safranin: 



C. vest. v. rubro-oc., moderate to moderately deep, value 65. 

 C. regnieri, moderate to moderately deep, lighter than in C. veatita 



var. rubro-oculata, value 60. 

 C. bryan, moderate to moderately deep, intermediate between the 



parents, value 63. 

 Temperature : 



C. vest. v. rubro-oc., in the majority at 72 to 74, in all at 74 to 75. 



mean 74.5. 

 C. regnieri, in the majority at 70 to 72, in all but rare grains at 



76 to 78, mean 77. 



C. bryan, in the majority at 72 to 74, in all but rare grains at 76 to 

 77, mean 76.5. 



C. vestita var. rubro-oculata exhibits a higher reactiv- 

 ity than the other parent in all five reactions, the differ- 

 ence being very marked in the polarization reactions; 

 slight in those with temperature ; and little in the others. 

 The hybrid C. bryan has intermediate reactivities be- 

 tween the parents in all of the reactions, being generally 

 somewhat closer to C. vestita var. rubro-ociilata than to 

 the other parent. 



Table A 46 shows the reaction-intensities in percent- 

 ages of total starch gelatinized at definite intervals (sec- 

 onds and minutes) : 



TABLE A 46. 



VELOCITY-REACTION CURVES. 



This section treats of the velocity-reaction curves of 

 the starches of Calanthe vestita var. rubro-oculata, C. 

 regnieri, and C. bryan, showing the quantitative differ- 

 ences in the behavior toward different reagents at definite 

 time-intervals. (Charts D 627 to D 634.) 



Among the most conspicuous features of these charts 

 are: The generally close correspondence in the courses of 

 all three curves. The well-marked separation of the 

 parental curves, even in the sulphuric-acid reactions, 

 which occur very quickly, there being as high a gelati- 

 nization of one parent in one-half a minute as in the 

 other in 5 minutes. The curve of C. vestita var. rubro- 

 oculata is lower than the curve of the other parent in all 

 of the 8 reactions. The curves of the hybrid show a 

 very marked tendency to intermediateness, and when not 

 mid-intermediate the inclination seems to be more 

 marked toward the pollen parent. In other reactions, in 

 one there is sameness, in relation to the seed parent and 

 in another the hybrid reaction is the highest of the three 

 and nearer the pollen parent. A tendency to an early 



