HARRIS: TETRACOTYLEDONOUS RACE OF PHASEOLUS VULGARIS 23 1 



seedling in 1913. Two of these died before maturity. Thus the 

 experiment was reduced to the progeny of seven plants none of which 

 have since been lost, alt hough the death rate in germination is 

 high, and a considerable proportion of the 191 3 plants died before 

 maturity or were killed by frost. 



TABLE I 



The seven pedigrees gave a total of 361 abnormal offspring^ 

 in 1914 and of 7,602 in 1915.^ 



In 1 91 2 there was no reason to distinguish -the 9 seedlings which 

 gave rise to the race here under consideration from any other of 

 the 4,286 abnormal ones secured in the germination of the 238,015 

 plants. They were quite naturally described by means of the 

 same schedule as the other plants. Because of the great variation 

 in the structural characteristics of bean seedlings, the classes of 

 these descriptive schedules were necessarily of a very general and 

 comprehensive nature. Had it been possible to foresee that 

 these plants would be particularly interesting because of their 

 progeny, each one would of course have been described and 

 figured in detail. 



According to the records of the schedule employed, only one of 

 the plants has a normal axis (Class I). Six were described as 

 slightly broadened (Class II) and two as very greatly broadened 

 or fasciated (Class III). 



In only a single case are the cotyledons described as normal in 

 number and insertion. In one seedling they were unrecorded. 

 In four seedlings they were three and in two cases four in number. 



1 Died in 1913. 



2 In addition to these three were three of questionable character and seven apparently 

 morphologically normal plants, which will be discussed below. 



*The actual number of plants in 1915 was somewhat higher, but because of the 

 pressure of other experimental work in the spring the sand in the seed pans could not 

 be worked over for plants which had died at an early stage in germination. 



'-t^- 



