ZOOLOGY AND BOTAXY, MICROSCOPY^ ETC. 420 



p. ScMzomycetes. 



Nucleus or nucleoid.bodies of Schizomycetes.* — Prof. M. Schottelius 

 claims that he is able to show that by suitable illiimiuation and in the 

 stained or unstained condition there exists iu bacilli a central nuclear 

 rodlet, and in cocci a central spherical nucleus. Beyond this point 

 he does not go ; that is, he does not conclude that these bodies arc 

 nuclei in the sense that word is used in when sj>eaking of the animal or 

 vegetable cell, but limits his definition, and merely designs to express 

 by it the central position of this piece of inspissated protoplasm. The 

 bacterium is thus divisible into three zones, an outer homogeneous almost 

 colourless sheath, next a greyish almost homogeneous zone, and finally in 

 the centre a delicate dark streak which somewhat resembles the axis- 

 cylinder in the sheath of a nerve-fibre. These thi'ee zones are observable 

 in the living condition, best in gelatin-drop-cultivations, or in clear agar. 

 The diflerentiation is still clearer in the stained condition; for this 

 purpose aqueous gentian-violet solution is the most suitable, the next most 

 eflective stain being fuchsin. ^^ ith these solutions cover-glass prepara- 

 tions are stained for l/-4-ly 2 minute, and the bacillus is shown to be 

 surrounded by an unstained homogeneous sheath. Xext comes the 

 stained contour of the protopLasm which is itself uncoloured ; next, and 

 lying centrally, is the dark, almost black nucleus-rod, having very often 

 a finely granular appearance as if composed of an aggregation of minute 

 granules. These ajipearances are, however, only to be obtained from 

 preparations of fresh viable individuals ; for when the bacillus dies its 

 nucleus splits up into various pieces. 



Micro-organisms of Msrtilus edulis.f — Dr. A. Lustig has been 

 attracted by the poisonous efiects of eating mussels to an examination 

 of its contained micro-organisms. He finds well-marked difterences 

 between specimens living in open sea-water and those found in stagnant 

 canals ; the former contain no microbes. The others have at least two, 

 one of which has pathogenetic eifects on certain Mammals, in which it 

 appears to cause enteritis. The proof that it is this microbe which 

 causes poisoning in Man can only be decided when the blood and vomit 

 of patients have been examined with the view of seeing whether the 

 microbe in question is there. 



Spore-formation in Bacillus Anthracis.i — Dr. A. M. Lewin has 

 investigated the question whether anthrax loses its spores after beincr 

 kept for some time at a high temperature. He comes to the conclusion 

 that anthrax vaccine contains no spores. He proceeded by taking strono- 

 cultivations of anthrax obtained from guinea-pigs just dead (36-48 hours 

 after inoculation) and keeping them at 42"— 13^ C. for 14-20 days. The 

 media were neutral bouillon and agar in test-tubes. Every day four 

 test-tubes were taken out of the thermostat and examined. One bouillon 

 and one agar tube were examined microscopically, and another pair were 

 kept for two hours at a temperature of 62-64^ C. in order to kill the 

 bacilli. If spores were really present the cultivations would still be 

 inoculable. Cover-glass preparations were then made and stained 

 by the Ehrlich-Koch method. The supposed spores were red (fuchsin), 



* Centralbl, f, Bakteriol. u. Parasitenk, iv. (ISSS) pp. 705-9. Cf. this Journal 

 1887, p. 1007. t Aicli. Itab Biol., x. (ISSS) pp. 393-400. 



j Wratsch. 18S7, pp. 70o and 739. Cf, Zeitschr. f. Wiss. Mikr.. v. fl888"i 

 pp. 39S-9. - V > 



