336 SUMMARY OF CURRENT RESEARCHES RELATING TO 
terised by the formation of a receptacle from this mass of swarm-cells in 
precisely the same w r ay as that of a Myxomycete from a true plasmode. 
The pseuclo-plasmode is formed by the swarming of true bacteria. 
In the case of Chondromyces (Myxobotrys), the bacterium is a rod, 
4-7 /x long, rounded at the ends, often irregularly bent, which possesses 
the power of swarming under certain conditions, forming a pseudo- 
plasmode about 1 mm. in diameter, which becomes invested by a gela- 
tinous envelope. Within this the greater part of the bacteria are used 
up in the formation of spores. Each rodlet increases in length, and 
divides by septa into from 4 to 6 cells, which round themselves off, 
invest themselves "with a rather thick membrane, and become the spores. 
According to the author, Thaxter’s generic name Myxobacter must 
give place to Polyangium, under which the organism has been described 
as the egg of an insect. A new species of Myxococcus, M. macrosporus, 
is described, growing on the batk of poplars. 
Crenothrix and Beggiatoa.* — According to Sig. G. Gasperini, the 
organisms known as Crenothrix Kiihniana and polyspora must be referred 
to Beggiatoa , a genus which has much more affinity with the lower 
filamentous Algse than with Bacteria. Beggiatoa will then include all 
the non-chlorophyllaceous forms w'hicli present the morphological and 
biological characters of the Oscillator iaceae. A similar affinity is dis- 
played by the forms included under the genera Streptothrix, Cladothrix,. 
Actinomyces , Thiothrix, Nocardia, Kurthia, Sphserotilus , Leptothrix, Lepto - 
tricilia, Detoniella, Hypheothrix, Basmussenia , and Phragmidiotlirix. 
When passed through iron tubes, Beggiatoa ( Crenothrix ) Kiihniana 
has the jDroperty of depositing iron in the form of a sheath of an organic 
ferric oxide, or of ferruginous tubercles. The usual colour of the flakes 
of this organism is ochroleucous or ochraceous, but it varies according to 
the quantity of iron deposited. 
Internal Structure of Micro-organisms. | — Herr V. Buzicka states 
that he has discovered important structural conditions in bacterial cells 
by means of a special though comparatively simple method. This 
method consists in fixing the cover-g^ass films in sublimate, staining with 
methylen-blue, and decolorising with acidulated water. By this method 
he has succeeded in demonstrating, in bacteria, fungi, and oidia, granules 
not hitherto described. The presence and size of the granules appear 
to depend largely on the age of the culture. In cocci the granules are 
usually central ; in rodlets, polar. Sometimes a rodlet may possess more 
than two granules ; if so, they may be situate at regular distances apart ; 
and if there be a single central one, it imparts the appearance of a 
nucleus, though it is not suggested that the central granule has a nuclear 
value. 
In fungi and in oidia the granules are more numerous and irregu- 
larly distributed. The same method also serves to demonstrate the 
septa where fission is taking place. 
Microbes of Root-Tubercles. J — M. Maze, who had previously shown 
that the fixation of nitrogen by the bacilli of Leguminosee is a property 
* Atti Soc. Tosc. Sci. Nat., xi. (1897, 8) pp. 3-7. 
t Central bl. Bakt. u. Par., l te Abt., xxiii. (1898) pp. 305-7 (1 pi.). 
t Ann. Inst. Pasteur, xii. (1898) pp. 1-25, 128-53 (2 pis.). Cf. tliis Journal, 
1897, p. 158. 
