was highest in sheaths and lowest in developing heads. Ash content of all plant parts except stems was higher in spring than in fall. Stems were only slightly lower in the spring. Percentage of silica in the ash was highest in the roots in spring, averaging 43.3%, and was lowest in developing heads (average of 9.80%).Spodograms representative of the silica deposition in various parts of the barley plants are shown in Figure 1. Considerable difference existed between the depositional pattern occurring in leaves and in sheaths. Rows of crenate edged silica particles, like those observed in barley sheaths, also, occurred in wheat sheaths (6, 8). The results showed no direct relationship between silica content and resistance to greenbugs, cold, or diseases. Both resistant and nonresistant varieties had high silica SELENIUM contents.There may be a relationship between early depositions and type of deposition to such resistance, as has been indicated by other workers.

The volatile selenium compound produced by cabbage (Brassica oleracea vat. Capitata) when cultured on media containing either selenite or selenate is dimethyl selenide, (CH3)2 Se. The dimetbyl selenide arises from enzymatic cleavage of a Se-methyl selenomethionine selenonium compound.

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