214 CLASSIFICATION OF RICE 



pore, Betul and Hoshangabad are quickly ripening rices sown in open 

 fields. 



Methods of ivork. — The line of attack has been by means of pure 

 cultures. Every rice received has been observed in cultures as 

 follows :^ — From each variety sent in, four of the largest and at the 

 same time most typical heads were selected. In a number of 

 instances where the sample was very impure, subordinate types were 

 selected ; in some cases as many as six were found necessary as for 

 instance in Sihia Bikia (Jubbulpore). Of these heads three were 

 mounted as herbarium specimens for reference, while the grains from 

 the fourth were removed and placed in an envelope preparatory to 

 sowing. The contents of each envelope were sown in a line and the 

 produce compared with the specimen on the herbarium sheet. 

 Where the produce differed from the type, further pure cultures 

 were made, heads being selected from the original sample, and at the 

 same time the types found in the produce were separated out as 

 indicated in the case of the original selection. In this way it was 

 possible to check results, and at the bame time to observe how far 

 natural crossing took place. So far no cases of natural crossing 

 have occurred in the Ime cultures. The occurrence of the grains 

 of a wild rice. Tart, in many samples of rice received from Raipur 

 together with the fact that the presence of Tari in a rice field is held 

 by the cultivators to lead to the deterioration of the crop suggests 

 however the occurrence of natural cross-pollination. This is parti- 

 cularly interesting on account of the occurrence of a similar pheno- 

 menon in Texas.(l) The presence of a small quantity of red rice 

 plants is sufficient to vitiate a white rice crop which can only be kept 

 pure by the weeding out of the red grains before sowing. Since 

 this preliminary note was written, Hector(2) has shown that natural 

 cross-pollination takes place at Dacca to an extent provisionally 

 estimated at 4 per cent. The absence of any cross-poUination at 

 Nagpur would seem to indicate that this only takes place under 

 certain hmited conditions. A further check was maintained by the 

 selection of the produce of the best hues for trials on large plots. 

 The produce of each of the original lines was compared and the best 



