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Large cell mutants were produced with high frequency when a haploid strain of Saccharomyces cerevisiae was cultured on a nutrient agar containing 500mg/l α-naphthaleneacetic acid (NAA). These mutants had no selective advantage in the presence of NAA. Biochemical and genetic analyses showed that most of these variants involve changes in genome structure.

Effect of a homothallism-controlling gene on sporulation was studied, using isogenic yeast strains carrying and not carrying D gene. In all cases tested, D gene showed distinct promotive effect on sporulation, irrespective of the period of incubation in presporulation or sporulation medium. However, D gene has no significant effect on vegetative growth in presporulation culture.

Apparent non-Mendelian segregation encountered in a cross between adenine independent and adenine dependent haploid strains is explicable by postulating a multiple genetic control of adenine formation. One of these genes, which arose by spontaneous mutation in a originally pink adenine dependent culture, is presumed to block adenine synthesis prior to those already present in the stock. The postulated ad3 mutation is not linked with the other adenine genes, which, when mutant, cause color production, but it is epistatic to them.

The electrical activity of the olfactory bulb (OB) was first clearly observed around 5 days after birth in albino rats it generally consisted of (a) rhythmic “induced” waves, appearing in bursts after inspiration, and (b) “intrinsic” waves of lower amplitude and fast frequency, occurring independently of nasal air flow. The first cortical activity was also observed around the same time, and was very similar to the OB activity, especially to the induced waves. This similarity, however, diminished daily as the rats grew. In adult rats, little correspondence between the two structures was found.A series of experiments suggested the dependence of the cortical activity upon OB induced waves because (1) the latter activity occurred with an almost fixed temporal relation to the former, (2) both cortical and OB activities were simultaneously enhanced in amplitude by (a) strong olfactory stimulation with amyl acetate or xylene as well as (b) higher doses (20 mg/kg) of pentobarbital injected intraperitoneally (i. p.), and (3) the cortical rhythmic activity, appearing in synchrony with the OB induced activity was almost completely abolished (a) when the inspired air was made to by-pass the nasal cavity and (b) after the OB was removed bilaterally.

Fresh egg white contained about 0.02% lipids, and 13–15% phospholipids for the lipids. They were made up of triglyceride, diglyceride, free fatty acid, cholesterol ester and cholesterol in acetone-soluble materials, and phosphatidylcholine (PC), lysophosphatidylcholine (LPC), phosphatidylethanolamine (PE), sphingomyelin (SPM) and unknown material with choline base in acetone-insoluble materials. Triglyceride was present in larger amounts. The amounts of PC, SPM, LPC and PE were 43, 32, 24% and trace, respectively. It was suggested that more than half of lipids were present in bound form with protein. Lipid contents in egg white slightly increased during storage at 30 ± 1°C. and 12 ± 1°C., but little increased at 4 ± 2°C. It was shown that no phospholipid but triglyceride and cholesterol ester might pass from egg yolk into albumen during storage.

Genetic control of the ability of yeast cells to respond to cell-expanding action of animal, plant and yeast hormones was studied. Mating type specificity in the ability to respond to yeast sexual hormones was changed by introduction of homothallism-controlling genes, D and HM. Auxin, a plant hormone can expand cells of most homothallic strains, but not those of heterothallic strains as far as tested. Animal sex hormones showed the action similar to that of yeast sexual hormones.