808 BOTANICAL GAZETTE. > 
the coccus form, and in some species thread forms which are produced by the ad- 
hesion of the co 0 Spore formation as yet undemonstrate 
Genera: Sir jococeus, Micrococcus, Ascococcus, Merismopedia, Sarcina. 
acteriacee. Possessing mostly cocci, rods (straight or curved), @ and 
thivad forms (straight or spiral). The first may be wanting; the latter have 
no distinction of base and apex. Division, so far as known, in one direction 
only. Spore tweiaiian existing, or wanting, or ae 
nada Bacterium, Spirillum, Vibrio, Leuconostoc, Bacillus, Clostridium. 
otriche. Possessing cocci, rods, and thread forms (which show @ 
distinetion “ base and apex). The latter straight or spiral. Spore formation 
not demonstrated. 
enera: Leptothriz, Beggiatoa,Crenothrixz, Phragmidiothriz. 
4, Cladotriches. Possessing cocci, rods, thread and spiral forms. The 
thread form is provided with false branches. Spore formation not yet demon 
strated, 
Genus: Cladothriz.—From Die Spaltpilze. 
Stopper for Bacteria Culture Vessel.—In recent numbers of = Nature 
meg Dr. H. Fol, of Geneva, Shaul described, among 
ey k. je other things pertaining to liiatesie, a permeable stop- 
per for culture vessels that has proved so valuable 
upon trial that we give an illustration and description 
of it. In most forms of culture vessels it is impossi- 4 A. 
ble to introduce or remove any substance without at ¥# 4 
the same time exposing the contents of the vessel in 
some degree to contamination from the germs of the 
air. In this form a small glass test tube an inch or 
so long, having a hole in the bottom, is wrapped with 
cotton and fitted into the mouth of the vessel. It is 
then half filled with glass wool or asbestos and pro- 
tected by a mass of cotton (Fig. 1). The contents of 
the vessel are easily reached by removing the plug of 
cotton and introducing a capillary glass tube (Fig. 2), 
glass wool offering little resistance to such a tube — Fig. 2 
while cotton can not be pierced. A translation of part of Dr. 
Fig. 1. Fol’s article has appeared in the Scientific American Su 
since the above was written the larger part of it has been given in Science.—J- 0. = 
Bacteria as Vegetable Parasites.—The only genuine instance of parasitic 
bacteria in plants yet mentioned by the books (DeBary, Zopf, etc.) is that of the 
yellow sickness of hyacinths, first described by Dr. Wakker, of Amsterdam, i 
1882. This bacterium winters in the bulb scales, and increases in the spring © 
slimy yellow masses which destroy the tissues and eventually kill the ae 
The priority of demonstrating parasitic bacteria in plants belongs. penn 
an American. In 1880, two years before Dr. Wakker’s ate of 
teria in hyacinths, Professor T. J. Burrill, of Illinois, presen 
