1040 
Journal of Agricultural Research 
Vol. XXVIII, No. 10 
The cultural characters were studied in direct comparison with those of 
Bacterium translucens , that is, the two organisms were run in parallel series. 
In all of these studies of cultural characters the two organisms were found to 
be identical. The results were the same as given for the barley organism, 
B. translucens, except in one detail as follows: In the case of action on starch, 
it was previously reported for the barley organism, B. translucens , that there 
was “no evidence of diastatic action on potato starch * * *” In the present 
investigations, using the more delicate methods described by Conn et al., 5 * it was 
found that both the barley organisms, B. translucens , and the new rye organism 
produced a very feeble diastatic action on starch noticeable for approximately 
half an hour after the iodin solution had been applied. After that time it was 
difficult to detect any halo about the colonies. There was possibly a slight 
dextrine reaction- 
in addition, certain special studies were made on indicator media. Sac¬ 
charine media containing brom cresol purple and cresol red, respectively, were 
prepared according to the recommendations of Conn et al. 5 
The new rye organism and the barley 7 organism, Bacterium translucens, were 
used in parallel series. Eight agar slants of each medium were inoculated with 
each organism respectively, and four slants of each medium were left uninocu- 
lated. Both organisms changed the color of each medium to the same degree 
in the same length of time. Alkaline reactions were produced in all of these 
media as follows: Pronounced in those containing lactose, maltose, mannit, or 
glycerine; less pronounced in those containing dextrose; and still less pronounced 
in those containing saccharose. 
On the basis of these studies it is evident that the new rye organism is identical 
with B. translucens and the previously described variety, B. translucens undur 
losum , both in morphological characters and in physiological characters in arti¬ 
ficial culture media but differs from both in pathogenicity. Hence, the new rye 
organism is here designated a new variety of B. translucens as follows: 
Bacterium translucens secalis n. var. 
In morphology and in artificial culture this variety is identical with Bacterium 
translucens and B. translucens undulosum . 
Bacterium translucens infects only barley. 
Bacterium translucens undulosum infects wheat, barley, rye, and spelt. 
Bacterium translucens secalis infects only rye. 
Type locality: Bloomington, Ill. 
5 Conn, H. J., and others. Report of the Committee on the Descriptive Chart for 1910. Jour • 
Bact. 5: 127-143; 315-319. 1920. 
