766 



DATA OF PROPERTIES OF STARCHES OF PARENT- AND HYBRID-STOCKS. 



than in C. lowianum, but less numerous than in C. ebur- 

 neum. The aggregates are of similar character to those 

 noted for both parents, but the components of doublets 

 are more often of equal size than in G. lowianum and 

 about the same as in C. eburneum; and the mosaics of 

 from 5 to 8 components are more often of rounded form 

 than in C. loivianum, but not so frequently as in C. ebur- 

 neum. The grains are not usually flattened as in the 

 parents. In form the grains of C. eburneo-lowianum are 

 slightly closer to C. lowianum than C. eburneum, but 

 there are only slight differences between the parents and 

 the hybrid. 



The hilum is not very distinct, and frequently is 

 undemonstrable, but much more often than in the 

 parents. It appears as a small, round or lenticular, non- 

 refractive spot. A small cavity is observed at the hilum 

 with slightly greater frequency than C. lowianum, but 

 much less often than in G. eburneum. Fissures at and 

 proceeding from the hilum are sometimes present, slightly 

 more often than in C. lowianum, and much less often 

 than in C. eburneum. These fissures have about the 

 same arrangement as that noted for C. eburneum. The 

 position of the hilum varies from centric to quite eccen- 

 tric. The range of eccentricity is usually from 0.44 to 

 0.25, commonly about 0.33, of the longitudinal axis, about 

 the same as in C. eburneum. Since the hilum is less 

 frequently demonstrable than in either parent, it is 

 possible that it was not different in grains in which the 

 eccentricity was greater than measurements given. In 

 the character of the hilum, C. eburneo-lowianum is 

 slightly closer to 0. lowianum but in the range of eccen- 

 tricity it is closer to G. eburneum. 



The lamellce are generally indistinct, and less often 

 demonstrable than in C. lowianum but somewhat more 

 frequently seen than in C. eburneum. When demon- 

 strable they have the same general structure and arrange- 

 ment as in both parents ; a secondary set of lamellae placed 

 at right angles to the primary set was observed as 

 in C. lowianum, this set not being noted in C. eburneum. 

 On the larger grains 12 to 16, commonly 14, may be 

 counted. In the character and number of the lamellae 

 C. eburneo-lowianum is slightly closer to C. lowianum 

 than to C. eburneum. 



The size varies from the smaller isolated grains of the 

 disaggregate type which are 3 by 2/x, to the larger iso- 

 lated grains of the same type which are 28 by 20/t, in 

 length and breadth. The common size is about 20 by 18/n. 

 The isolated grains of the aggregate type vary from 5 

 by 4/u. to 16 by 14/* in length and breadth; the common 

 size being 10 by 9/t in length and breadth. There are 

 many more of these smaller grains of this type than in 

 C. lowianum, hence the mean size is less than in this 

 species, although nearer to this species than to C. ebur- 

 neum. In size the grains of C. eburneo-lowianum are 

 closer to C. lowianum but in proportion of length to 

 breadth they are closer to G. eburneum. 



Polariscopic Properties. 

 The figure varies from centric to quite eccentric as 

 in both parents, but those of the quite eccentric type are 

 less frequent than in G. lowianum, but considerably more 

 numerous than in C. eburneum. The character and the 

 arrangement of the lines are about the same as in both 



parents. Double and multiple figures are observed, but 

 they are somewhat less numerous than in the parents. 



The degree of polarization is high (value 80). It is 

 the same as in C. lowianum, and higher than in C. ebur- 

 neum. The grains vary somewhat from high to very 

 high, and there is more variation in the different grains 

 than in either parent. 



With selenite the quadrants are sharply defined, as in 

 both parents. They are generally somewhat less unequal 

 in size than in C. lowianum; but nearer this species than 

 G. eburneum. They are more often regular though they 

 may be somewhat irregular, as in both parents. The 

 colors are generally pure, the same as in G. lowianum, the 

 yellow more often pure than in C. eburneum. 



In degree of polarization, character of the figure, and 

 appearances with selenite the grains of G. eburneo- 

 lowianum are closer to C. lowianum than to C. eburneum. 



Iodine Reactions. 

 With 0.25 per cent Lugol's solution the grains color 

 a moderate violet (value 50) with a little more of a red- 

 dish tint than in G. lowianum, but nearer the color of 

 this species than in C. eburneum. The color deepens, 

 becoming more bluish, and changing with somewhat 

 greater rapidity than in the parents. With 0.125 per 

 cent Lugol's solution the grains color a light violet of 

 the same depth but with more of a reddish tint than in 

 G. lowianum, and a little lighter and less reddish than in 

 C. eburneum. The color deepens to moderately deep, 

 reaching a greater depth with somewhat more rapidity 

 than in the parents. After heating in water until all the 

 grains are gelatinized and then adding 2 per cent Lugol's 

 solution the grains become a moderately deep, bright 

 indigo-blue, many with a tint of red. The color is deeper 

 and less reddish than in C. lowianum, and lighter and 

 less reddish than in G. eburneum. The solution is 

 colored deeper than in C. lowianum, and about as deep 

 as in C. eburneum, but nearer the tint of C. lowianum. 

 If the preparation is boiled for 2 minutes and then 

 treated with, 2 per cent Lugol's solution the grain-residues 

 color a light to a moderate blue with reddish tint, lighter 

 than in the parents. They are far more numerous than 

 in C. lowianum, but about as in G. eburneum. Most of 

 the capsules color a deep old-rose to deep reddish-helio- 

 trope, and a few wine-red; they are colored deeper but 

 not quite so red as in C. lowianum, but decidedly more 

 reddish than in C. eburneum. A greater variation in 

 tint exists than in either parent. The solution is colored 

 about the same as in C. lowianum, but slightly deeper 

 than in C. eburneum. In the reaction with iodine C. 

 eburneo-lowianum shows a closer relationship to C. lowi- 

 anum than to G. eburneum. 



Aniline Reactions. 



With gentian violet most of the grains color lightly 

 immediately, a few moderately. In 30 minutes they are 

 light to moderately deep (value 55), the majority being 

 moderate. There is a greater variation but the mean is 

 the same as in C. lowianum, while the variation is about 

 the same, but the mean color slightly lighter than in 

 C. eburneum. 



With safranvn the grains immediately color light to 

 moderate, mostly the former, the reaction being the same 

 as in G. lowiamim, but slightly lighter than in C. ebur- 



