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IOWA ACADEMY OF SCIENCES. 
The miracles of the “Bloody Host” of the first part of 
the Christian Era are familiar to every one. The sacra- 
mental bread was rich in starch and poor in acid so it gave 
a good medium for the development of the B. prodigiosus 
germs. The priests of the middle ages knew how to make 
the most of such a striking phenomenon. In recent times, 
during the siege of Paris, large quantities of bread became 
red through the action and growth of B. jirodigiosiis. 
Blue milk, green and yellow milk are all facts that have 
been noted by our forefathers but today scientists have 
proved such color changes to be due to various chromo- 
genic bacteria. A number of blue chromogenes occur in 
water, milk and liquids. Chester names several. Other 
blue organisms have been described by Hueppe, Stern- 
berg, etc., yet thus far only ten species have been found 
in our Iowa flora. B. violaceus latirentiiis and Micrococcus 
cyanogenus are some of them. The latter Doctor Pammel 
and Mr. Combs have described as follows: 
Source, — During the latter part of May, 1894, a foreign 
blue color was observed in an old milk culture of an organ- 
ism obtained from cheese; later the same was found in an 
old milk culture of B. aroynaticus. A transfer from, the 
first milk tube was made to another tube of sterilized 
milk, the typical color appearing in three or four days. 
The organism was separated by pouring plates of agar. 
Morphology , — A small micrococcus occurring singly or 
in groups; motility not determined. An aerobic liquefy- 
ing micrococcus. 
Agur. — Nearly colorless, with a slight tinge of blue, pro- 
ducing an irregular film on the surface. Grows at the 
temperature of the room. 
Gelatin. — A creamy white layer not spreading on surface, 
soon liquefying, forming a funnel shaped area, later the 
medium was liquefied with a creamy white sediment in the 
bottom of the tube. 
Milk. — Sterilized milk inoculated produces in three 
days a slight blue layer on surface, which increases in 
intensity, becoming quite blue for one third of an inch on 
