ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 635 



Schizophy ta. 

 Schizomycetes. 



Appearance found in certain Bacteria when Examined by the 

 Indian-ink Method.* — (J. Sangiorgi calls attention to an appearance 

 seen in bacteria when examined by tbe indian-ink method. In the centre 

 of the cell, whether of the coccus or bacillus shape, appears a dark in- 

 clusion of the same shade as that of the film, and which is therefore in 

 marked contrast with the bright body of the bacterium. The character 

 of the cultivation medium makes no difference, but the appearances are 

 more frequent in young germs than in older ones. The effect of acetic 

 acid and of NOH (1 : 1000) is unfavourable, but dilutions of 1 : 10,000 

 and upward seem to make no difference. Bacteria killed by boiling do 

 not exhibit the phenomenon. The appearance seems to be associated 

 with the growth and vitality of the organisms. 



Chemical and Bacteriological Study of Fresh Eggs.t — Mary E. 

 Pennington examined fifty-seven eggs, and found that seven only were 

 sterile ; in the remainder, bacteria, of which thirty-six varieties were 

 identified, were present, both in white and yolk. The chemical data 

 relate mainly to nitrogenous compounds in both white and yolk : nitrogen 

 coagulable by heat, in filtrate, tannic acid precipitate, etc. These details 

 are given in numerous tables. 



Endotoxin of Micrococcus melitensis.^ — P. N. Bernard finds from 

 animal experiment that bouillon cultures do not become toxic before 

 the fifteenth day. Heated cultures when kept increase in toxicity with 

 age, and after 85 days are twenty times as toxic as cultures of the same 

 age when not heated. The endotoxin is unaffected by heating to 58°C. 

 for 1 hour ; the toxicity is diminished by a temperature of 80°. "When 

 boiled for 5 minutes the fluid is ten times less toxic than the original ; 

 prolonged heating completely destroys the toxin. 



Biological and Chemical Studies on Nitroso-bacteria.§ — G. E. 

 Clage records experiments made with Pseudomonas radicicola for the 

 purpose of investigating its nitrogen-fixation when growing in symbiosis 

 with Trifolium pratense. The experiments showed that Pseudomonas 

 radicicola can be isolated from the soil, carried through inoculation experi- 

 ments, and recovered in a pure state. By cultivating weak strains on 

 nitrogen-free media the nitrogen-fixing property is considerably exalted. 

 Of sugars, maltose suited the organism best. When grown on media 

 containing less than 5 C atoms no gum is produced. In very old cul- 

 tures, especially on solid media, P. radicicola develops a membrane which 

 appears cell-like in structure, but does not give the cellulose and starch 

 reactions. Subcultures from these may produce considerable nitrite and 



* Centralbl. Bakt., lte Abt. Orig., lv. (1910) pp. 94-6 (2 figs.). 

 t Journ. Biol. Chern., vii. (1910) pp. 109-32, through Journ. Chem. Soc.,xcvii. 

 and xcviii , ii. 224. % C.R Soc. Biol. Paris, lxix. (1910) pp. 36-8. 



§ Centralbl. Bakt., 2te Abt., xxvii.(1909) pp. 7-48. 



2 U 2 



