336 
and the two years under consideration were exceptional in the fact 
that their number was far in excess of those I have seen in past years. 
Plehn, at the British Medical Association Meeting in 1908, made 
the statement that the longest period that the crescents are found in 
the blood was six weeks; but in two of my cases they were found 
exactly for two months, and in one of them the last date cannot be 
determined, as the patient absconded from the hospital. Further, 
one has to consider the fact that we have no means of determining 
the date of the first appearance of the crescents in the blood, as all 
the patients were admitted in a very advanced state of the disease. 
Thus the total duration of the existence of these parasites must be 
more than two months. 
Another statement by the same author concerns the diagnosis of 
such cases with crescents by increased urobilin in the urine. The 
use of an alcoholic solution of zinc acetate and Lugol’s solution is 
described by him as the most delicate test. Both these points 1 was 
not able to confirm in my series of cases. Many of these crescents 
cases showed no increase of urobilin except in the very early stage, 
and generally at this stage the rings are still present, so that the 
urobilin is to be attributed rather to the blood destruction by the 
rings than to the presence of the crescents. 
Of the two cases which showed crescents for two months, one 
lad ’ from the start ver y few, and still they persisted for the time 
stated. 1 his patient had only quinine treatment. The other had a 
very heavy infection, and when admitted was moribund, and so was 
put on picric acid treatment, but as she hardly ever swallowed her 
medicine, injections of picrate of soda had to be resorted to for a 
lew days during the second month, and then the crescents soon 
disappeared. 
he injections ot piciate of soda were not found to produce any 
qmcker results than the method of administration of picric acd by 
he mouth ; however, m the case mentioned above it was necessary, as 
the pattern would not take the medicines readily. 
The method of preparing the solution of picrate of soda for 
injection is as follows : - 
drop’ a mJ.g .olotion'of’TodLm "hydrate ratine'th'? < ‘““ llcd “ d t0 ,h “ add > dr °P b > 
”f di-methyl-amido-azo-benzol till the iSte „„ loLrram, red" m “ m ' “"t '"t T'Tl 
turn* red and siihs«.riii<.r.el.. ( i i S turns rcd - (do not stop when the dimethyl 
subsequently fades, but go on adding the sodium hydrate solution till no change of 
