Dysentery amebae may live for 72 hours in vitro. The transition of the large vegetative forms into the cyst may be observed in vitro. The large vegetative ameba always passes into an intermediate stage before assuming the small vegetative form. The atypical forms are dysentery amebas with abnormal nuclei and cytoplasm. When circumstances are unfavorable encystment takes place. Under favorable c...

Spores and vegetative forms of a strain of B. megatherium were irradiated by ultraviolet light of the wave lengths 2536 A, 2803 A, and 3132 A. The killing rate of both bacteria and spores is exponential, in agreement with irradiation results on other bacteria. Twice as much incident energy is needed to kill the spores as the vegetative forms (50 per cent death). The absorbed energy per bacteriu...

Vegetative characters are widely used in the taxonomy of the amphibious genus Elatine L. However, these usually show great variation not just between species but between their aquatic and terrestrial forms. In the present study we examine the variation of seed and vegetative characters in nine Elatine species (E. brachysperma, E. californica, E. gussonei, E. hexandra, E. hungarica, E. hydropipe...

Aspergillus niger forms aerial hyphae and conidiophores after a period of vegetative growth. The hyphae within the mycelium of A. niger are divided by septa. The central pore in these septa allows for cytoplasmic streaming. Here, we studied inter- and intra-compartmental streaming of the reporter protein GFP in A. niger. Expression of the gene encoding nuclear targeted GFP from the gpdA or glaA...

The exact position of the actinomycetes or ray-fungi in the kingdom of lower forms of life has attracted considerable attention and has been a subject of much speculation. These organisms have been classified as bacteria, as fungi, and as a special group, either derived from one of the above or giving rise to both. With the accumulated knowledge concerning the morphology of the actinomycetes, i...