4 Experiments in Crossing a Wild Pea from Palestine with Commercial Peas. 



crosses were generally smaller in size than is usual in the seeds of the seed-bearing 

 parent, and frequently the cotyledons were so badly developed as to make the 

 seed-coat appear almost empty. In the reverse case, when the Palestine Pea was 

 used as the seed-bearing parent, the resulting seeds of the crosses were like those 

 of the Palestine Pea, but sometimes of a larger size. 



Plants. 



In Fl the hybrid plants were generally taller than those of the Palestine Pea, 

 but when a very tall Pea (nearly 6J feet in height) was used in the cross they did 



not reach the height of this taller parent. 

 This fact may perhaps be explained by the 

 weakness of the hybrids, which would prob- 

 ably have grown more freely and attained 

 a greater height had they been raised entirely 

 under glass. 



Coloured flowers were dominant over 

 white flowers. 



The serration of the leaves in a modified 

 form was generally observed in all plants 

 in Fl ; in some plants it was absent in 

 F2. No plants resembling the parental 

 Palestine Pea in form but with white blooms 

 were noticed ; if any were produced they 

 probably died off prematurely. 



The pods of the hybrids were usually 

 very small, sometimes smaller than those 

 of the Palestine Pea itself ; they were 

 badly developed, in most cases " puffy " 

 with a woolly substance inside (as in 

 Feves), and were practically sterile. Those 

 which were fertile were only partially so, 

 although this feature of sterility seems 

 to a certain extent to have been overcome 

 in the cases of those hybrids still under culture in F4. 



Generally some segregation occurred in F2, but as many of the plants were 

 by no means well developed and consequently died off, and the experiments were 

 undertaken with a view to ascertaining (if possible) the relationship of this Wild 

 Palestine Pea to the cultivated types, rather than to test Mendelian laws, these 

 results give us no profitable return. 



It cannot be claimed as a result of my experiments that the Palestine Pea is 5 

 certainly the forerunner of present-day garden Peas, for whilst on the one hand the 

 fact that some of the hybrids are fertile and have been grown on to F4 might not 

 preclude such a possibility, yet, on the other hand, the colour of the flowers, the 

 serrated leaflets, the woolly nature of the interior of the pod, the type of seed, and 

 the sterility of most of the hybrids would perhaps point to its not being so. 



The failure to set seed in some cases may possibly be due to the difficulty of = 



.* 



Tig. 3 Pods and foliage of an ordinary 

 commercial small-podded variety of cul- 

 inary Pea, for comparison with Fig. 2. 



