80 
SUMMARY OF OURRENT RESEARCHES RELATING TO 
intensity of the light. And not only do differences and variations in 
the intensity of the light affect these bacteria, but they are sensitive to 
differences of wave-length ; this sensitiveness depending on the species, 
the individuality, and external conditions. In addition to visible rays, 
they are affected by certain ultra-red radiations ; so that mobile forms will 
gather together in the ultra-red between A. 0 • 90 and 0 • 80. They also 
collect in other bands, but in decreasing quantity between X 0*61-0 ‘58, 
X 0*55-0*52, X 0*75-0*64, and in the ultra-violet. From this dis- 
position a “ bacteriospectrogram ” is formed by the bacteria themselves 
beneath the cover-glass. 
Spectroscopic examination of the colour, and calculations as to the 
absorption of the dark heat-rays by these bacteria, were carefully made 
by the author, who sums up the results in tables, for which the original 
must be consulted. 
That the purple bacteria give off oxygen under the influence of light 
was demonstrated from the zoogloea conditions of D. pJioto^netricum, Monas 
vinosa, Warmingi, Oheni, and Clatlirocystis roseo-persicina. As tests it 
was necessary to employ Schizomycetes very sensitive to oxygen. In 
the result it was found that these purple Schizomycetes occupy a place 
among those organisms which assimilate after the manner of green 
plants, and that bacterio-purpurin may be considered a true chromo- 
phyll ; inasmuch as, after having absorbed the actual energy of the light, 
it transforms it into potential chemical energy. In conclusion, the 
relations between the assimilation and absorption of rays of different 
wave-lengths by bacterio-purpurin are entered into. Put shortly, this 
may be summed up as the more light the more oxygen, and the most 
striking proof of this was furnished by the experiments with the ultra- 
red rays. Here all visible rays were occluded by means of a 4 cm. 
layer of bisulphide of carbon. These experiments also show that the 
disengagement of oxygen is not connected with the action of the visible 
rays, but that the dark rays are equally capable of setting free oxygen. 
New Capsule Bacillus.* — Dr. Pfeiffer found in the abdomen of a 
guinea-pig a puriform exudation, which was found not to consist of pus, 
but to be a pure cultivation of bacilli, which were also found in 
considerable quantity in the blood. 
These bacilli have rounded ends, and are arranged in longer or 
shorter filaments. They are enveloped in a capsule, wherefore the 
author proposes to call them Bacillus capsulatus. They are not endowed 
with motion. They grow luxuriantly on gelatin, agar, bouillon, and 
potato. They do not liquefy gelatin. They are pathogenic for both 
white and house mice, these animals dying in two or three days. After 
death the bacillus is discoverable in all the organs and juices of the body. 
Guinea-pigs and pigeons could be infected from the peritoneal cavity, 
but rabbits through the circulation only. This bacillus is said to be 
easily distinguishable from the pneumonia bacillus and the pseudo- 
pneumonia bacillus. 
Bacterium phosphorescens.t — Prof. K. B. Lehmann, who, in con- 
junction with Dr. P. Tollhausen, has been making some experiments 
* Zeitschr. f. Hygiene, vi. (1889) p. 145. 
t Centralbl. f. liakteriol. u. Parasitenk., v. (1889) pp. 785-91. 
