BREEDING AND SEED IMPROVEMENT /I 



Gregory 1 studied the historical nature of differ- 

 ences between round and wrinkled peas, basing 

 work on Mendel's experiments. He found that 

 round peas, which included indented sugar peas, 

 have the central tissues of the cotyledons filled 

 with very large starch grains. In the same region 

 the starch grains of wrinkled peas are of a decidedly 

 different type, frequently being compound. 



Interesting facts relative to weight and specific 

 gravity of pea seed is given by Andree. 2 He 

 learned the lightest peas are always found near both 

 ends of the pod. The average weight of a pea in a 

 pod was greater the larger the number of peas in 

 the pod, so that the largest pods contain the heav- 

 iest peas. The weight of peas next the point of 

 pod increased with the increased number of peas 

 in the pod. However, with exception of the first 

 and last peas, there was but a very small difference 

 in the weight of the peas in the same pod. Experi- 

 ments as to specific gravity were, in general, com- 

 parable with those found for weights. In general 

 practice, however, he believes it is not necessary to 

 pay much attention to specific gravity in selecting 

 seed. 



X E. s. R., Vol. 16. 



2 E. S. R., Vol. 5. 



