C. A. BARBER 143 



With actively growing seedlings another method has been adopted which 

 it is hoped will lead to more satisfactory agreement with the comparative 

 leaf width at crop time. This consists in viewing well-grown plants of the same 

 age at a short distance, estimating the average leaf width and measuring a 

 leaf which seems to rej)resent this average. The following are variations 

 recently obtained in this manner, Ashy Mauritius (150) 0-7" — 1-9", Striked 

 Mauritius (500) 0-8"— ] -7", Chynia (60) 0-8"— 1-75", Pansahi (250) 0-7"— 1-2", 

 Chin (200) 0-25" — 0-90". This method of judging the average is not very 

 applicable to mature seedlings, because of their height and general inacces- 

 sibility. 



Colour of the Leaves. 



There is considerable difference in the leaf colour of different varieties 

 and species of Saccharum. Saccharum spontaneuin has bluish green leaveS; 

 Saccharum arundiyiaceum light grass green and Saccharum Narenga has more of 

 a brownish tinge in the green, as grown at Coimbatore. Kafha has glaucous 

 green leaves and is thus readily distinguished from Dhaulu of Gurdaspur 

 in which the bluish colour is less apparent, while members of the Nargori 

 group may be. frequently distinguished by a peculiar coj^pery brown tinge. 

 In thick canes there are similar variations in tint which appear to be of taxo- 

 nomic value. Among the seedlings examined, a glaucous tint is often met 

 with in those of Chin parentage, and occurs in most of the seedlings which 

 have Saccharum spoyitaneum blood in them. Some of the seedlings of Java-, 

 Striped Mauritius, B 208 and Saretha have a marked purple tinge in the leaves, 

 and in the two former varieties this colour invades the midrib, which becomes, 

 in the absence of green there, a strong violet. Besides this, there are colora- 

 tions due to the invasion of specific fungi, which seem to occur in certain 

 seedlings and not in others. Stri^jing of the leaves has not as yet been met 

 with in the seedlings of indigenous canes, but it appears occasionally in seed- 

 lings of thicker canes. In B 20S, Striped Mauritius, Java and some others, 

 striped leaves occur regularly in about 2% of their seedlings. This is pro- 

 bably connected with incipient striping of the stems, a very rare occurrence 

 in seedling canes (c/. uiider colour of canes, p. 146). 



A marked difference can sometimes be noted between seedlings with 

 dark green leaves and those of lighter, yellowish green, but this difference may 

 be either inherent or due to alkalinity or salinity of the soil or irrigation water, 

 and this fact makes it necessary to exercise some care in classifying the seed- 

 lings according to this character. There is hardly anything in which cane 

 varieties differ more than in their capacity for resisting excess of salts in the 

 soil and, as there is a good deal of salinity in the Cane-breeding Station, this 



