ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
499 
formation was not observed. The microbes were easily stained with 
the usual anilin dyes. The same micro-organism was detected in 
material sent from the olive plantations of Puglia, Calabria, about 
Vesuvius, and Sorrento. 
Three series of inoculation experiments were made, and their 
results were that healthy olive plants raised from seed and not from 
cuttings, showed tumours in four or five weeks, while the control plants 
were unaffected. Secondly, that other kinds of plants inoculated with 
this bacillus never showed any kind of tumour. Thirdly, that olives 
inoculated with micro-organisms pathogenic to other plants were 
unaffected. Hence the author concludes that the Bacillus Oleae tuber- 
culosis is the specific cause of this disease of olive trees. 
Influence of the kind of Nutriment of a Bacillus on the Diastase 
secreted by it.* — M. W. Vignal has found, from a series of experiments 
which he has made from some bouillon cultivations of Bacillus mesen- 
tericus vulgatus , that up to a certain degree the nutrient media exert a 
definite influence on the quantity of the excretory products secreted by 
this bacillus. This influence made itself appreciable to a slight degree 
on the addition of sugar or starchy material, and to a significant extent 
on the addition of casein. The excretory products always quickly dis- 
appeared from the cultivation fluids. 
Bacillus mesentericus vulgatus. f — In a long monograph, M. W. 
Vignal treats exhaustively of the potato bacillus. He discusses its wide 
diffusion in water, in air, in the digestive system, its morphological, 
biological, and cultivation characters, and the way in which it is propa- 
gated and multiplies. The author then passes on to the influence which 
warmth and antiseptic media exert on the potato bacillus, and describes 
the changes which the bacillus induces in albuminous substances, 
gelatin, casein, sugar, starch, and vegetable matter, and concludes with 
remarks on the products of metabolism. 
Existence of Micro-organisms in the Tissues of the higher 
Plants.^ — M. E. Laurent, in reviewing the connection of bacteria and 
the higher plants, points out that while there are few bacterial affections 
among plants, there are a great number in the animal kingdom. In 
animals, the bacteria overcome the resistance of the living cells by the 
production of toxic matter, which is rapidly diffused throughout the 
organism by the blood, while in plants the migrations of these parasites 
and their secretions is more difficult. The author sums up the results 
of his own experiments, and also those of others, as to the existence of 
foreign organisms within vegetable tissues, by denying the possibility of 
their existence under normal conditions. But although this statement 
is to be regarded as true for most cases, exceptions to the rule are pointed 
out. Thus several Nostocacem live within the tissues of various living 
plants, while a more remarkable example of symbiosis between vascular 
plants and microbes is offered by the Leguminosaa. 
* Archiv de Med. Experiment, et d’Anat. Pathol., 1889, p. 517. Cf. Centralbl. 
f. Bakteriol. u. Parasitenk., vii. (1890) p. 61. 
t ‘ Contributions a l’etude des Bacteriacees,’ Paris, 1889. Cf. Centralbl. f. 
Bakteriol. u. Parasitenk., vii (1S90) pp. 61--2. 
X Bull. Sue. Roy. Bot. de Belgique, xxviii. (1889) pp. 233-14. 
