ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 487 



ill." It is a coarse-looking rod with rounded ends, sometimes elongating 

 into a thread, or it may be into a chain of rods. Its breadth is over 

 1 p, and in length it varies from 3-12 /* or more ; it is feebly motile, 

 and forms spores with central or polar location. 



It is an essential anaerobe, and grows best on alkalin-glucose broth 

 and glucose-gelatin covered with oil. During germination a gas with 

 putrefactive odour is evolved. 



Italian Variety of Nitrosomonas europaea.* — R. Perotti obtained 

 samples of earth from different parts of Italy, and isolated therefrom in 

 Omelianski's medium (amnion, sulph. 2, sodium chloride 2, potass. 

 phosphate 1, magnesium sulphate 0*5, iron sulphate 0*4, distilled 

 water 1000) a variety of Nitrosomonas with similar morphological 

 characters. It mostly occurred as a small coccus * 6-0 • 8 fi in diameter, 

 but showed indications of transition to bacillus form. In the monad 

 stage the organism possesses a flagellum equal in length to the bacterial 

 body. The movements are slow and jerky. It does not develop in 

 media containing organic substances ; it produces nitrous acid from the 

 salts of ammonium. 



Bacillus alatus sp. n.t — R. Greig-Smith found this pleomorphic slime 

 bacterium when isolating Rhizobium leguminosarum from the nodules of 

 Lupinus luteus. It is a motile rodlet with numerous periorichous flagella. 

 When stained with fuchsin it is acid-fast to 5 p.c. HC1, but is negative 

 to Gram. The shape and size of the capsule vary with the medium. 

 It forms indol and reduces nitrates to nitrites, and coagulates milk at 

 55° C. On certain media with a vegetable base it forms a slime readily 

 and luxuriantly ; from the slime was obtained a thick mucilage with 

 the reactions of arabin. The gum seems from its reactions to lie 

 between Macrozamia gum and Gum Acacia. 



Identity of Opsonins and Normal Agglutinins.:}: — R. Greig-Smith 

 finds that opsonins and agglutinins have many points of similarity, and 

 probably no points of difference. The similarities are : (1) Staphylo- 

 coccus opsonin and agglutinin are not destroyed at 60° C. — their powers 

 are only in abeyance. Contact with the bacteria for 20 hours induces a 

 recovery. (2) In dilute saline solutions the recovery of the opsonic 

 power is accompanied by an agglutination of the bacteria. (3) Potassium 

 chloride gives a greater agglutinative and a greater opsonic effect than 

 sodium chloride. (4) Dilution of the serum with saline solutions 

 increases the agglutinative and the relative opsonic effects. (5) Longer 

 cultivation of a weak race of staphylococcus increases the agglutinability 

 and the opsonisation of the cells. 



Opsonisation appears to be the first phase of agglutination. 



Phagocytosis in vitro.§ — M. Lohlein undertook some experiments 

 to confirm Metchnikoff's work on the ingestion of pathogenic organisms 



* Atti R. Accad. Lincei, xv. (1906) pp. 512-16. 



+ Proc. Linn. Soc, N.S.W., xxx. (1906) pp. 570-3 (1 pi.). 



% Tom. cit., pp. 555-69. 



§ Ann. Inst. Pasteur, xix. (1905) p. 647. 



