680 
ROBERT H. WILSON. 
Mallease .—Mallease is a preparation used in the precipitin 
test for the diagnosis of glanders. It is prepared by dissolving 
the glanders bacteria in a 7 or 8 per cent solution of antiformin, 
neutralizing the solution after 2 hours with 5 per cent, sulphuric 
acid and then filtering through paper and Berkefeld filter. The 
active principal of the solution is known as precipitinogen, which 
has the property of combining with the antibody, precipitin and 
forming a precipitate. According to Konew, who devised the 
precipitin test for glanders, the formation of precipitins in the 
fluids of the body begin at the time of the entrance of the infec¬ 
tious agent, which apparently indicates that the test should be 
valuable in detecting the disease at the onset. To carry out the 
test 1 c.c. or any small amount of the mallease is placed in a 
slender test tube. Then about the same amount of the serum 
under test is taken in a pipette, which is inserted into the mallease 
solution until it reaches the bottom of the test tube. The serum 
is permitted to escape slowly under the mallease so that the two 
will not mix, a sharp line of separation dividing the two fluids. 
If the serum is from a glanders animal a precipitate, in the form 
of a white ring, will appear at the line of separation, the density 
of the ring, and the time necessary for its formation usually de¬ 
pending upon the severity of the case. The precipitate is the 
result of the interaction of the precipitin in the serum and the 
precipitinogen contained in the mallease. The time required for 
the test varies from a few minutes to an hour or more. 
This'test gives fairly uniform results in practice, although 
occasionally the ring which forms is rather indistinct and leaves 
the operator in doubt as to the diagnosis. Field experiments 
with the test conducted by our laboratory, show that in the ma¬ 
jority of cases it confirms the results of the mallein and ag¬ 
glutination tests. 
The complement fixation test that has been recently employed 
for the diagnosis of several animal diseases, particularly gland¬ 
ers, is dependent on several products of biologic origin. For the 
glanders test they would be an extract of the glanders organism 
(antigen), the blood of a rabbit which has been immunized to 
