x, B, 2 Barber and Jones: Coccobacillus acridiorum d’Herelle 167 
of mature locusts was inoculated, and from the first or second 
dying in this series, an agar culture was made from the leg. 
It had then been passed through 14 series of insects, the last 
two immediately before the experiment. 
The stock culture had been transferred about four times on 
agar and kept at room temperature for about six weeks. A 
broth emulsion was made of a 10-hour agar culture of this 
stock strain and a similar emulsion of the “exalted” strain. 
With a fine, very sharp capillary pipette, approximately 
equal doses of each emulsion were inoculated into the abdominal 
cavity of mature locusts recently taken from the field. The dose 
was gauged by a mark on the pipette, and the same pipette was 
used for all inoculations. It was sterilized in hot water after 
the inoculation’ of each lot. The size of the dose was larger, 
if there was any material difference, for the exalted strain 
than for the stock culture, and the exalted strain was inoculated 
after the stock, so that any growth taking place in the broth ~ 
would tend to make the exalted strain larger. The aim was 
to have any error in the direction of increasing the exalted 
culture corrected. The dose of the exalted culture, as measured 
in the Thoma Zeiss counting chamber, approximated 2 cubic 
millimeters; and by measuring the dimensions of the lumen of the 
capillary, approximately the same result was obtained. The 
number of bacteria per dose roughly approximated 1,500,000. 
Fifty locusts were inoculated with each strain, and as con- 
trols, 50 were inoculated with the same dose of sterile broth 
and 50 were placed in a cage with no treatment. 
The four lots were placed in separate cages under similar 
conditions. The results are given in Table I. 
TABLE I.—Locusts inoculated with Coccobacillus acridiorum. 












oe py | 
Locusts dead or moribund at the end of— 
Lo- if : res. 
Lot Dose, about 2 cubic milli- SEIS 
, a in- Hours. Days. 
No. | meters of loeu- | , 
lated.| l t 
| | MR, | PAs, | BY 25 3} 4 Ds le 17. 
feealiStocke culture == === =ae | SO} 2h) 0) By) Bu BA) 40) Gu ze aan | 
2___| Exalted strain, 14 insect pas- 
RACES. A eee es 50 i 5 21 34 44 AGMM ATE eaten | scales 
Sees WBrochialones =) ee ae ee BO ease 1 1 3 6 uf 7 || 1 
4___| No inoculation ---_--_-_------ Oe oe 1 1 2 4 5 5 Sie, | 
| A ni ia | 5 








a All dead. 
The table shows that the insects died somewhat sooner from 
the dose of the exalted strain than from that of the stock 
