Diffusion coefficients of vitamins B12 and B12a. Bruno Jaselskis, Joseph F. Foster, and Harvey Diehl 1

Histology of the maize plant in relation to susceptibility to the European corn borer. Max E. Bell 9

Effects of differential testosterone propionate levels on rat accessory gland activity. L.F. Cavazos and R.M. Melampy 19

Electrical conductance studies on an ion exchange resin. R.P. Puri, Frederick R. Duke, and June Lomnes 25

A study of mixed gas adsorption on mercury. Robert S. Hanson and Doris V. Stage 33

Passage of cherry virus through Prunus root grafts. O. F. HOBART, JR. 49 F.ull sib and parent offspring correlations in symmetrical random mating populations with the frequency of the more favorable allele the same at all loci. Theodore W. Horner 55

The components of variance in symmetrical random mating populations with the frequency of the more favorable allele the same at all loci. TheodoreE W. Horner 67

Measurements of the unsporulated oocysts of Eimeria acervulina, E. maxima, E. tenella, and E. mitis; coccidian parasites of the common fowl. E.R. Becker 85