344 BACTERIA IN RELATION TO PLANT DISEASES. 
THE PARASITE. 
Bacterium hyacinthi* Wakker is readily isolated. In the plant and on agar and in beef- 
broth, etc., it is a short rod, single or in pairs, or more rarely in fours joined end to end 
(figs. 139, 140). Rarely short chains have been observed, e. g., on agar. It measures under 
these circumstances 0.4 to 0.6 4 X0.8 to 2 uw, but like many other organisms, it is longer or 
shorter, thicker or thinner, according to age, culture-medium, and kind of stain used. Itisgen- 
erally slenderer than Bact. campestre or Bact. phaseoli. $Thefollowing are some measurements: 
(1) February 5, 1898. Slime from a daughter-bulb 
stained 5 minutes in a saturated solution of basic fuchsin 
(very weak stain). Rods short, 0.5 to 1.0 X0.4 to 0.5m. 
‘Two minutes in saturated watery solution of Gentian violet 
gave a deeper stain but not deep enough. 
(2) February 7, 1898. Alkaline beef-broth, No. 1, Jan- 
uary 29, 1898, stained 10 minutes in saturated watery 
solution of basic fuchsin. 
-OX0O.4u 
-4 xe single rods. 
-OX0.4p 
.6X0o.4u two rods joined end to end. 
.2X0.4u two rods joined end to end. 
Widest rods seen 0. 6. 
(3) July 31, 1898. Slide of March 1o from very dilute 
beef-broth 3 days old, Moore’s flagella stain. Size 1 to2X 
0.5 to0.7M. Flagella 3 times length of rods. 
(4) August 3,1898. Slide of March 17, 1897, agar stock 
207, Fischer’s flagella stain: 
2Xo.8u 2to3X1.op. 
2X1.0n 2.5 Xo0.8 to 1.0 several. 
(5) August 3, 1898. Slide of June 23, 1897, made from 
the interior of a bulb (yellow slime). Plant inoculated on 
leaf February 16, 1897. Stain, basic fuchsin in water. 
WW eH eb 
1.0X0.5u two; 1.5 X0.5u; 1.2X0.5u; Most 1 to 1.2X0.5y; 
Extremes, 0.9 to 1.5 XO. 5nu. 
Pseudozoogloez are common. No spores have 
been discovered by the writer, and the spores described 
by Wakker probably belonged to some other organ- 
ism.t This is the more likely because the cultures in 
which they developed abundantly were made directly 
from the bulb, 7. e., not from colonies, and were kept 
at a temperature slightly above the maximum for the 
growth of this organism, as determined by the writer. 
Fig. 137.t Making cultures from bulb scales in the same way as 
Dr. Wakker, the writer has twice obtained mixed 
growths from what looked like an unmixed source; the yellow organism being contaminated 
once by a green fluorescent organism and once by a white, gas-forming species. In the 
plant and in the common culture media chains and filaments do not occur, or are rare, but 
old cultures on media rich in sugar, e. g., streaks on dextrose-agar or saccharose-agar, often 
*Synonyms: Bacillus hyacinthi (Wakker) Trevisan; Pseudomonas hyacinthi (Wakker) EFS. 
+The endospores observed by Wakker were blue-shining, strongly refractive bodies, germinating equatorially. 
They were cylindric with rounded ends, measuring 14 in length and being about one-half or two-thirds as thick. 
They sometimes appeared at temperatures lower than 35° C., but less abundantly. 
tFic. 137.—Cross-section of a hyacinth-leaf showing xylem part of the bundle occupied by a bacterial cavity, 
parenchyma to either side being unoccupied. Leaf inoculated at apex in 1898 with a culture of Bact. hyacinthi. To 
either side of the bundle are (C C) natural passage-ways through leaf. Slide 502 B-A7. 
