ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
345 
grow by acropetal apical growth. When short the segments resemble 
bacilli or cocci ; the joints separate at the septa. This, the author 
points out, is an excellent example of the rule that it should not be 
assumed that an organism is a Schizomycete because it is small, grows 
on gelatin, and can be stained. 
Spore-formation of Bacterium coli commune.* * * § — Dr. E. Piccoli has 
observed an instance of spore-formation by B. coli commune , when culti- 
vated in broth at 35° for twenty-eight days. The spores were oval, 
1 • 5 /a long and 1 p broad. They were either quite free, or attached 
to one end of a bacillus. Examination of the material in hanging drop 
cultivations showed that the bacteria were mobile. Cultivations made 
on various media, and under very variable conditions, failed to reproduce 
the spore-formation, but showed that the bacterium was really B. coli 
commune. The source of the original cultivation was the excrement of 
a healthy man. 
New Pathogenic Bacillus. j- — Mr. L. H. Pammel describes the 
injuries done to the crops of beet and turnips in Iowa by the attacks of 
a new form of bacillus to which he gives the name B. campestris. It 
consists of motile rods 1*87-3 x 0*37 p, rounded at the end, and 
occurring singly or in chains. 
Heredity of Acquired Immunity.} — Prof. L. Vaillard makes an 
important contribution to the subject of acquired immunity. The 
experiments were made on animals immunised to tetanus, cholera, 
anthrax, and the disease produced by the Vibrio avicida. The immu- 
nising procedures adopted were those in common use, viz. for tetanus, 
progressively increasing injections of toxin modified by iodine, and 
afterwards active toxin ; for anthrax, the method of Cbamberland and 
Eoux ; for cholera, progressively increasing injections of cultures heated 
to 100° ; for the Vibrio avicida , subcutaneous inoculation of graduated 
doses of virulent cultures. The animals used were rabbits and guinea- 
pigs. Erom his observations the author deduces three principal facts. 
Only the mother is able to transmit immunity to the offspring ; the 
father never does. The immunity received from the parent is always 
of short duration, and is lost in the first few months of life. These 
results are opposed to the view that hereditary immunity is due to the 
accumulation of immunities or resistances, acquired from having been 
handed down through a long series of generations ; and though it was 
found that one parent can impart immunity, the force of this is much 
diminished by the early disappearance of the preservative influence. 
Cladothrix odorifera.§ — Dr. Kullmann has recently found Cladothrix 
odorifera in several kinds of earths, and always with the same characters 
as he had previously ascribed to it. Cl. odorifera and Cl. dichotoma 
were found growing on the same plate, and were differentiated by the 
former browning the gelatin and developing the characteristic earthy 
smell. It would appear, however, that when bread-pap and starch- 
paste, which are very suitable for cultivating Cladothrix, are used, 
* Centralbl. f. Bakteriol. u. Parasitenk., l te Abt., xix. (1896) pp. 307-13 (1 fig.). 
f Iowa Agric. Coll. Exp.-Stat., 1895, Bull. No. 27. 
% Ann. Inst. Pasteur, x. (1896) pp. 65-85. 
§ Centralbl. f. Bakteriol. u. Parasitenk., 2 te Abt., ii. (1896) pp. 116-7. 
