510 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
Stutzer, and others, which does not agree with his own, is based on 
errors of observation. According to the author, the nitrification of 
organic nitrogen is not perfected by pure cultures of nitrification 
bacteria. These organisms have absolutely no power of attacking 
nitrogenous organic substances, either by splitting off ammonia or by 
immediate oxidation of the organic nitrogen. For the nitrification of 
organic nitrogen it is indispensable that it should first be mineralised, 
that is to say, converted into ammonia, and for this the co-operation of 
at least one micro-organism is requisite by which organic substances 
are decomposed with the formation of ammonia. 
Fermentation of Barbary Figs.* — M. E. Rolants states that the 
Barbary fig ( Cactus Opuntia ) may be advantageously employed for the 
industrial manufacture of alcohol. The yield of alcohol at 100° was 
found to be from 40-60 litres per 1000 kilos of fruit, according to the 
richness of the fruit in fermentable sugar. The yeasts used were six 
in number, those yielding the best returns being a Logos yeast and a 
cliampagne-wine ferment. 
Curing and Fermentation of Cigar-leaf Tobacco. f — According to 
Dr. O. Loew, the so-called tobacco fermentation is not caused by bacteria, 
the principal changes that take place during the curing and fermenting 
of tobacco being due to the action of soluble ferments or enzymes. In 
the curing process four enzymes co-operate — an amylolytic and proteo- 
lytic, and two oxidising, while in the fermenting process the main changes 
are due to oxidising enzymes, and consist in the oxidation of nicotine 
and other compounds. 
In green tobacco two oxidising enzymes may exist, an oxydase and 
a peroxydase. The development of colour and aroma is principally due 
to the action of the oxidising enzymes. 
7* General. 
Terminology of Spores.J — M. P. van Tieghem proposes to limit the 
term spore to those cells which are formed on an adult plant, and which 
develop into a new adult individual. All the Fungi and most Algae 
form spores ; the propagules of the Bryophyta are spores ; but no 
vascular plants form spores. The term diode is suggested for repro- 
ductive bodies arising on the adult which develop into a rudimentary 
body ; the prothallium thus establishing a transition between the adult 
aud the rudimentary stages. Thallophytes and Bryophytes have no 
diodes ; they belong only to vascular plants, which may hence be termed 
Diodophytes or Prothallacese. Diodes may be all alike ( isodiodes ), or 
they may be differentiated (lieterodiodes ) into microdiodes and macro- 
diodes. They are usually formed in groups surrounded by one or more 
layers of sterile cells, forming a diodange. 
All the Bryophyta, the Florideae, and the Mucorini, produce cells 
which are not spores, because they do not arise on the adult stage, 
nor diodes, because they produce directly the adult form ; for these 
van Tieghem proposes the term tomie, and the rudimentary structure on 
* Ann. Inst. Pasteur, xiii. (1899) pp. 452-5. 
t U.S. Dept, of Agriculture, Rep. No. 59, 1899, 34 pp. 
X Journ. de Bot. (Morot), xiii. (1899) pp. 137-42. 
