ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
371 
Influence of Light on Bacteria.* — Herr E. Koltjar has made some 
experiments in the laboratory of Prof. Batalin, of St. Petersburg, as to 
the influence of light on Bac. pseudo-anthracis [sic], Sarcina aurantiaca, 
Micrococcus prodigiosus, and a raspberry-red coccus. Coloured rays 
were obtained by passing the light through stained gelatin with which 
the test-tubes were covered. The cultivation media were agar and 
potato. The author did not notice that the attendant heat exerted any 
inhibitory influence. The action of the heat-rays was not examined. 
Sunlight prevented the growth of these non-pathogenic bacteria, but not 
to the extent which has been described by other observers for pathogenic 
species. Of the coloured rays the red are favourable to growth, the 
violet prevent it, yet less so than white sunlight does. The differences of 
pigment production in the chromogenous bacteria exactly accord with 
the luxuriance of their growth. The author made the interesting obser- 
vation that the violet rays favour the sporulation of Bac. pseudanthracis. 
Diastatic and Inverting Ferments of Bacteria. f — Dr. C. Feroni 
gives the results of further experiments on bacterial ferments. From 
these he desired to ascertain if there were microbes other than those 
already examined by him which possess a diastatic action ; if the bacteria 
generate their ferment action in the presence of substances which contain 
no proteids; and whether any bacteria are capable of inverting cane- 
sugar, lactose, and maltose into dextrose, levulose, and galactose. 
(1) Of 38 new species examined, only 11 possessed a diastatic action. 
(2) Eleven formed acid. (3) The Streptothrix species (e. g. Actinomyces ), 
except St. carnea, all formed a diastatic ferment. (4) Many microbes 
secrete a diastatic ferment without forming acid ; others produce acid, 
but have no ferment action. (5) On media devoid of albumen, none 
of the bacteria produced a trace of diastatic ferment. (6) None of the 
glucoside was changed into sugar. (7) Of 62 different species of micro- 
organisms, only the Kiel bacillus and Bacillus megaterium inverted, and 
about 50 produced acid ; all the Streptothrix cultures had an alkaline 
reaction. (8) Of the 62 species examined, 24 formed a proteolytic, 
20 a diastatic, and 2 an inverting ferment. Thus, 46 out of 62 microbes 
possess a ferment. Of these 46 species, 10 form the proteolytic alone, 
13 the diastatic alone, and 18 two ferments ; Bac. megaterium produces 
all three ferments. (9) Definite relations between the formation of 
individual ferments and the formation of acid, of pigment, the mobility 
of the microbes, and their morphological structure, could not be 
made out. 
Leuconostoc mesenterioides.]; — According to Herr C. Liesenberg 
the organism which is so destructive to cane sugar in the Indies, and 
especially in Java, is morphologically and physiologically the same as 
the frog-spawn fungus. This organism causes a disease in the beet- 
juice used for producing beet sugar in Europe. So that, considering that 
the differences between the two merely consist in slight differences in 
rapidity of growth and in the optimum temperature, the Indian fungus 
* Wratsch, 1892, Nos. 39 and 40. See Centralbl. f. Bakteriol. u. Parasitenk 
xii. (1892) p. 836. 
f Centralbl. f. Bakteriol. u. Parasitenk., xii. (1892) pp. 713-5. 
x Beitr. z. Pliys. u. Morph, niederer Organismen (Zopf), 1892, No. 1 (2 pis ) See 
Bot. Centralbl., lii. (1892) pp. 59-60. 
2 c 2 
