16 
Same treatment as No. 7. 
GUINEA PIG NO. 8. 
Litter No. 1. 
July 29, 1905. 8A, 8B, and 8C born. 8B and 8C died. 
September 15. 8A given 0.22 c. c. toxine No. 7 + 1 immunity unit Ehrlich 15. VIII 
.05. Died in 7 days and 7 hours. Control died in 4 days. 
Litter No. 2. 
March 15, 1906. 8D, 8E, and 8F born. 
April 27. 8D given 0.22 c. c. toxine No. 7 + 1 immunity unit Ehrlich 15. VIII .06. 
No reaction. Control died in 4 days and 8 hours. 
April 27. 8E and 8F given same injection as 8D. Both died on the third day. 
Controls died on the third day. 
Litter No. 3. 
May 20, 1906. 8G, 8H, and 81 born. 
June 22. 8G and 8H given 0.05 toxine No. 7 (MLD = 0.006 c. c. ). 8G died in 1 day 
and 4 hours. Control died in 22 hours. 8H showed slight induration on third 
day. Recovered. Control died in 1 day and 4 hours. 
A Study of the above results shows that the young of all the mothers 
that were treated by repeated injections of the toxine-antitoxin mix- 
ture had a marked resistance to an L+ dose; all survived except one, 
4B, which died, but lived 3 day^s longer than the control. Four (4D, 
5E, 6D, and 6G) withstood one and a third times the L+ dose; this 
dose uniformly caused the death of the controls in less than 2 days. 
Four (5F, 5G, 6H, and 61) resisted one and a fourth times the L+ dose. 
Of four pigs tested against eight and a third times the MLD three 
recovered (4E, 4F, and 8H); one (8G) showed the average susceptibility 
to the toxine. 
The members of the fourth litter are as resistant as those of the 
first. The immunity seems to be greater in those pigs born of mothers 
treated with the toxine-antitoxin mixture than in those treated with 
the antitoxin alone. Pigs Nos. 4, 5, and 6 received a total of only 6 
units, given in doses of 1 unit plus an amount of toxine slightly greater 
than the L° dose, while pigs 7 and 8 received 4,250 units. Of seven 
young of these last two mothers, three recovered, one lived 3 days 
longer than the control, and three showed no resistance. 
Moreover, it would seem that the immunity produced by T the injec- 
tion of large amounts of antitoxin alone is not as lasting as that pro- 
duced by r small amounts plus small doses of toxine. 
IMMUNITY NOT TRANSMITTED TO SECOND GENERATION. 
Two female guinea pigs born of mother No. 6 (see p. 15). and from 
a litter of which the other members had shown marked resistance to 
diphtheria toxine, were placed with a male pig born of untreated 
parents. Each female had two young. These were given an L+ dose 
