MILTONIA CYMBIDIUM. 



133 



deficit in relation to the parents. (Table A 43 and Charts 

 D 595 toD 609.) 



The reactivities of the hybrid are the same as those 

 of the seed parent in the reactions with iodine, sai'ranin, 

 and potassium sulphocyanate ; the same as those of the 

 pollen parent in none; the same as those of both parents 

 in those with sulphuric acid, hydrochloric acid, and 

 potassium hydroxide, in all of which gelatinization occurs 

 very quickly; intermediate, but nearer the seed parent, in 

 that with chloral hydrate; highest with polarization, 

 chromic acid, pyrogallic acid, nitric acid, potassium io- 

 dide, potassium sulphide, sodium hydroxide, sodium sul- 

 phide, sodium salicylate, calcium nitrate, uranium 

 nitrate, strontium nitrate, cobalt nitrate, copper nitrate, 

 cupric chloride, copper chloride, barium chloride, and 

 mercuric chloride (in 14 being closer to the seed parent, 

 in 2 closer to the pollen parent, and in 1 as close to one as 

 to the other parent) ; and lowest with gentian violet and 

 temperature, in both being closer to the seed parent in 

 the latter practically the same. 



The following is a summary of the reaction-intensi- 

 ties:- Same as seed parent, 3; same as pollen parent, 0; 

 same as both parents, 3; intermediate, 1; highest, 17; 

 lowest, 2. 



Two very conspicuous features of these data are the 

 very markedly dominating influence of the seed parent 

 on the properties of the starch of the hybrid, and the 

 equally marked tendency to reactivities of the hybrid, 

 higher than those of the parents. In 20 out of the 26 

 reactions the seed parent is the same or closer to the 

 hybrid, while in only 2 is there closeness to the pollen 

 parent; and in 17 reactions the hybrid exceeds the reac- 

 tivities of the parents. 



COMPOSITE CURVES OF REACTION-INTENSITIES. 



This section treats of the composite curves of the 

 reaction-intensities, showing the differentiation of the 

 starches of Miltonia vexillaria, M. rcezlii, and M. bleuana. 

 (Chart E 43.) 



The most conspicuous features of this chart arc : The 

 close correspondence in the rises and falls of all three 

 curves excepting in the reactions with gentian violet, 

 chloral hydrate, and calcium nitrate. In the gentian- 

 violet reactions the curves of M. vexillaria and the hybrid 

 fall, while the curve of M. rcezlii rises; in the chloral- 

 hydrate reactions the curves of the former rise while the 

 curve of the latter falls ; and in the calcium-nitrate reac- 

 tions the curve of M. rcezlii appears aberrant by falling. 

 M. vexillaria has higher reactivities than the other parent 

 in the reactions with polarization, iodine, choral hy- 

 drate, pyrogallic acid, potassium iodide, potassium sul- 

 phocyanate, potassium sulphide, sodium hydroxide, 

 calcium nitrate, strontium nitrate, copper nitrate, cupric 

 chloride, and mercuric chloride ; lower reactivities with 

 gentian violet, safranin, temperature, cobalt nitrate, and 

 barium chloride; and the same or practically the same 

 reaction-intensities with chromic acid, nitric acid, sul- 

 phuric acid, hydrochloric acid, potassium hydroxide, 

 sodium sulphide, sodium salicylate, and uranium nitrate. 

 In M. vexillaria the very high reactions with polarization, 

 nitric acid, sulphuric acid, hydrochloric acid, potassium 

 hydroxide, potassium iodide, potassium sulphocyanate, 

 sodium hydroxide, sodium salicylate, calcium nitrate, 

 strontium nitrate, and copper nitrate ; the high reactions 

 with chloral hydrate, chromic acid, sodium sulphide, and 

 uranium nitrate; the moderate reactions with iodine, 

 gentian violet, safranin, pyrogallic acid, and potassium 

 sulphide; the low reactions with temperature, cobalt 

 nitrate, cupric chloride, and mercuric chloride : and the 

 very low reactions with barium chloride. In M. rcezlii 

 the very high reactions with nitric acid, sulphuric acid, 



hydrochloric acid, potassium hydroxide, potassium sul- 

 phocyanate, sodium salicylate, and strontium nitrate; 

 the high reactions with polarization, safranin, chromic 

 acid, sodium hydroxide, sodium sulphide, uranium 

 nitrate, and copper nitrate ; the moderate reactions with 

 iodine, gentian violet, temperature, potassium iodide, 

 and calcium nitrate ; the low reactions with chloral 

 hydrate, pyrogallic acid, potassium sulphide, cobalt ni- 

 trate, cupric chloride, and mercuric chloride; and the 

 very low reactions with barium chloride. In M. bleuana, 

 the very high reactions with polarization, chromic acid, 

 nitric acid, sulphuric acid, hydrochloric acid, potassium 

 hydroxide, potassium iodide, potassium sulphocyanate, 

 potassium sulphide, sodium hydroxide, sodium sulphide, 

 sodium salicylate, calcium nitrate, uranium nitrate, 

 strontium nitrate, and copper nitrate; the high reac- 

 tions with chloral hydrate, pyrogallic acid, cupric chlo- 

 ride, and mercuric chloride; the moderate reactions with 

 iodine, gentian violet, safranin, and cobalt nitrate; the 

 low reaction with temperature; and the very low reac- 

 tion with barium chloride. 



Following is a summary of the reaction-intensities: 



44. COMPARISON OF THE STARCHES OF CYMBIDIUM 

 LOWIANUM, C. EBUENEUM, AND C. EBUENEO- 

 LOWIANUM. 



In the histologic characteristics, polariscopic figures, 

 reactions with selenite, qualitative reactions with iodine, 

 and qualitative reactions with the various chemical rea- 

 gents all three starches exhibit properties in common in 

 varying degrees of development together with certain 

 individualities which collectively are in each case char- 

 acteristic. The starch of Cymbidium lowinaum in com- 

 parison with that of C. eburneum has somewhat less 

 numerous grains of the disaggregate type ; pressure facets 

 on separated grains are more numerous ; the surfaces of 

 disaggregates are more regular; large grains of the iso 

 lated disaggregate type are more numerous and more 

 varied in form ; compactly arranged triplets and quad- 

 ruplets are more common; components of doublets are 

 more often of equal size ; and mosaics of five to ten com- 

 ponents are more rounded. The hilum has a cavity 

 or cleft more often ; it is more often fissured ; there are 

 various modifications of fissuring; eccentricity is less. 

 The lamellae are much less often demonstrable ; there is 

 an absence of a secondary set of lamellae at right angle 

 to the primary set; the number is probably less. The 

 size is on the whole smaller, and differences are noted 

 in the proportion of length to width. In the polariscopic, 

 selenite, and qualitative iodine reactions various differ- 

 ences are recorded in the three starches, mostly appa- 

 rently of a very minor character. In the qualitative 

 reactions with chloral hydrate, chromic acid, nitric acid, 

 potassium hydroxide, potassium iodide, potassium sul- 

 phocyanate, and sodium salicylate various points of dif- 

 ference have been demonstrated, but these seem to be of 

 minor character. Throughout, with few exceptions, the 

 hybrid is much closer to C. lowianum. 



Reaction-intensities Expressed by Light, Color, and Tempera- 

 ture Reactions. 

 Polarization: 



C. lowianum, high, value 80. 



C. eburneum, high, lower than in C. lowianum, value 75. 



C. eburn.-low., high, the same a3 in C. lowianum, value 80. 



