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.-[■'\ , This race and all the folio j^i^ing ones except a red sugar 

 .corn, I got from the Agricultural College of our university. 

 * Amber rice pop corn ' has very small ears and kernels, the 

 latter being of reddish amber like color and of a long, pointed 

 beaked form. The number of gemini of this race is generally 10 

 (Figs. 12, 13, 14). The differences of their size and shape are 

 not so remarkable as in the preceding two races. But two 

 types of forms could be clearly observed; the one was like a 

 ring, while the other like a rod. The number of gemini of the 

 'former type is about 6 and that of the latter 4, and here also 

 two equal sets of gemini can be recognized (Figs. 12, 14). At 

 the later metaphese they make their appearances in different 

 shapes according to different parts of the bodies of chromo- 

 somes, where they are grasped by the spindle fibres (Fig. 13). 



Abnormal Cask : Although the number of gemini in this 

 race was generally 10 as I have above stated, I was astonished 

 to come arcoss a much larger number. In one pollen mother cell 

 the gemini were counted as many as 20 (Fig. 16). They were 

 much smaller than the normal ones, and somewhat of the shape 

 of a dumb-bells. From the consideration of the case of Fig. 15, 

 in which all the gemini are more or less thinner than the normal 

 ones and each geminus shows several knots, this phenomenon 

 is likely to be looked upon as a separation of geminial chromo- 

 somes by themselves, without intervention of the traction fibres. 

 The cases of failure of chromosomes to pair in the pollen 

 mother cells were often reported. Among them Hieracium ex- 

 cellens (4), Houttuynia cordata (6), Some forms of Rosa (5), 

 Oenothera (1), &q. may be mentioned. But in my case the 

 separation takes place twice and apparently in transverse 

 manner. In the second separation, however, some or majority 

 •of chromosomes may remain forming geiiiini (Fig. 17). In such 

 a: nuclear division the chromosomes dre separated into two 

 approximately equal groups and make their journey towards 

 the poles, where the spindle fibres are scarcely observed. At 



