24 TECHNICAL BVLLETIX 134, U. S. DEPT. OF AGRICULTURE 
of P. C. 727A, dried in an electric oven, was 500 millip-ams per kilo 
of body weight, and that of P. C. 724 A iuid of P. C. 725 A, dried in a 
steam oven, was the same. 
Sample P. C. 760 in the second run and P. C. 775 in the fourth run 
were made at SO^ C, and both were more toxic than P. C. 770 in the 
tliird run. which was held at 40^ to 50^ for three days before being 
heated to SO^. This suggests that a rapid rise to s6° for the fresh 
bulb tends to produce the most toxic squill powder. 
The rate of drying was followed only until uniform weight was 
indicated. At SO^ C. it seems that drying would be complete in about 
three days. 
Although food containmg 40 per cent of squill powder was readily 
eaten, 10 per cent concentrations were used in most instances. With 
this concentration, a rat consuming 1 per cent of its body weight of 
food would consume 0.1 per cent of its body weight of squill, or 1,000 
milligrams of squill per kilo. Accordingly, squill preparations having 
a lethal dose at or below 1,000 milhgrams per kilo appear to be 
sufficiently toxic for commercial purposes. Most of the experimental 
powders killed in materially smaller doses. 
The production under semicommercial conditions on a semicommer- 
cial scale of squill powders ha\'ing similar toxicities indicates the 
possibility of successfully manufacturing squill powdei-s of a satis- 
factory degree of toxicity on a commercial basis. 
RELATIVE SLSCEPTIBnJTY OF WHITE RATS AND OF ^TLD (BROWN) RATS TO SQUILL 
POWDERS 
From the literature it would seem that wild (brown) rats are more 
susceptible to squill than white rats. The lethal doses found in the 
investigations here reported, when the same powder was fed to the 
two forms, are given in Table 11. 
Table 11. — Relative susceptibiliiy of white rats and of tcild (brown) rats to squill 
powders 
Sample Xo. 
Minimum lethal 
dose for — 
-V^^. per 
j kijm. of 
body 
P. C. I weight 
16. J 750 
18 500 
3S 250 
719AF I 2,000 
720 A 250 
720B 250 
721 A 350 
722A 500+ 
Average- 
Minimum lethal 
j dose for — 
White 
rats 
Wild 
rats 
A/j7. per 
Mg. per 
kgm. of 
kgm. of 
body 
body 
weight 
weight 
1, 000+ 
500 
(2.0+) 
500 
500 
1.0 
750 
500 
1.5 
500 
300+ 
(1.7-) 
625 
500 
1.3 
500 
500+ 
(1.0-) 
1.5 
In some series no difference in susceptibility was noted; in others 
the wild rats appeared to be about three times as sensitive. Lack of 
material and the difficulty of obtaining a fairly large supply of wild 
rats for feeding purposes at any definite time prevented more accurate 
determinations of differences in susceptibility of the two forms. 
