222 EXPERIMENT STATION RECORD. 



to 400 cf tbe seeds plante<l, a ratio not agreeing witli tlie Mendellan hypothesis. 

 The new form is better adapted tlian is the parent form to withstand in- 

 fluences imfavorable to germination. 



The author thinlis that selective germination and differential mortality 

 among dormant seeds may be important factors in natural selection. He 

 also holds that mutation is a process distinct from Mendelian segregation, 

 and that the phenomena exhibited by (E. lamurckiana, (E. 'bienn'm, and (E. 

 pratincola can not be attribute<l to heterozygosis. 



Cultural bud mutations in subterranean portions of Solanum caldasii, E. 

 Heckel {Compt. Rend. Acad. Sd. [Paris], IGO (1915), ^^o. 1, pp. 2//-2S).— In 

 continuance of previous articles (E. S. R., 30, pp. 433, 529, 730), the author 

 reports "that he has obtained, from the same stock of 8. caldasii, tubers some 

 of which resembled the wild ancestors while others resembled in several 

 respects cultivated varieties. This is considered a case of mutation. 



The effect of salt on the growth of Salicomia, A. C. Halket (Ann. Dot. 

 [London], 29 {1915), No. 11,1, pp. I.'f3-15.'i, pi. 1, figs. Jf). — A series of experi- 

 ments was conducted with Salicornia and Suseda seedlings which were culti- 

 vated in the presence of various amounts of sodium chlorid, some being grown 

 in soil treated with solutions containing various percentages of sea salt, while 

 others were grown in nuti'itive solutions to which definite quantities of sodium 

 chlorid were added. 



The author found that Salicornia oliveri and S. ramosissima grow better in 

 the presence of sodium chlorid than in its absence, the greatest growth taking 

 place when between 2 and 3 per cent of this salt was present. With higher 

 percentages of salt there was a decrease in the growth of the plants. The 

 effect of sodium chlorid on the growth of Suwda maritima was not so marked, 

 the plants growing as well in its absence as when a small quantity (1 per 

 cent) was present. Both Salicomia ramosissima and Suwda maritima were 

 found able to resist the presence of a large amount of sodium chlorid, the 

 plants remaining alive and green with the salinity of water in the soil at 

 times as high as 17 per cent, although they were not able to make any growth. 



The growth of Glyceria maritima was found to decrease with an increase 

 of salinity in the soil. 



The total amino nitrogen in the seedlings of the Alaska pea, T. G. Thomp- 

 son (Jour. A7ncr. Chem. Soc, 37 (1915), No. 1, pp. 230-235). — An account is 

 given of a study of the formation and distribution of amino acids and the acid 

 amids in seedlings of the Alaska pea at various stages of growth (especially in 

 the very young seedlings). 



The author states that there is a steady increase in tlie percentage of amino 

 nitrogen and a notable increase thereof on the first and the fifth day. This is 

 explained as probably due to the rapid transformation of the seed and the re- 

 quirement for a greater quantity of this sort of plant food to build up the 

 highly elaborated nitrogenous material in leaves, stems, and roots. In case of 

 seven-day seedlings it was found that the plumules contained a much greater 

 amount of amino nitrogen, supposedly serving as a food supply for the newly 

 forming leaves and stems. 



Analysis of leaves and of stem near the top and near the roots of the plant 

 showed that the total nitrogen remains fairly constant in the leaves, but that 

 there is a noticeable decrease in the amino nitrogen. With increase in age the 

 leaves and stems near the top and bottom show a decrease in both total and 

 amino nitrogen when expressed in terms of dry material. The amino nitrogen 

 in the stems near the lower part of the plant shows a slightly smaller per- 

 centage than is noted in the sample taken near the leaves. Results from the 



