The first * to draw especial attention to branching and budding forms of the tubercle bacillus were Nocard and Roux (1) in 1887. In the following year Metchnikoff (2) described and figured long, threadlike, branching forms with bulbous ends, observed in old glycerineagar cultfires cultivated at 43.6o-44 ° C. It is probable that these were cultures from avian tuberculosis. )/[etchnikoff suggeste...

After introducing some cohomology classes as obstructions to orientation and spin structures etc., we explain some applications of cohomology to physical problems, in especial to reduced holonomy in M and F -theories.