676 
GENETICS: R. PEARL 
Owing to various reasons, which cannot be gone into here, ether 
has been dropped from the list of experimental agents, ethyl and methyl 
alcohols alone being used now. 
A detailed account of the experimental methods used and the pre- 
cautions taken to ensure accuracy and trustworthiness of results is 
given in the complete reports now in press. 
2. The general results of the 1916 matings, so far as concern the 
chief characters which may be taken as indices of vigor and vitality, 
are set forth in Table 1. 
TABLE 1 
Showing the Mortality (Prenatal and Postnatal) of Chicks of Alcoholic Ancestry, 
AS Compared with Those of Non-Alcoholic Ancestry 
Matings in 1916 
NATURE OF ANCESTRY 
NUMBER 
OF MAT- 
INGS 
TOTAL 
EGGS 
SET 
TOTAL 
ZYGOTES 
FORMED 
ZYGOTES 
FORMED 
PRENA- 
TAL MOR- 
TALITY 
POST- 
NATAL 
(180 
DAY) 
MORTAL- 
ITY 
ZYGOTES 
ALIVE 
AT 180 
DAYS OF 
AGE 
per cent 
per cent 
per cent 
Both parents alcoholic 
5 
82 
18 
21.95 
11.11 
25.00 
66.67 
3 
63 
5 
7.94 
80.00 
0 
20.00 
Sire only alcohoUc 
13 
512 
274 
53.52 
47.08 
13.79 
45.62 
Sire and one or more grandparents al- 
3 
233 
158 
67.81 
46.84 
28.38 
39.87 
One or more grandparents alcoholic. . . 
3 
187 
113 
60.43 
46.02 
6.56 
50.44 
All of alcoholic ancestry 
27 
1077 
568 
52.74 
45.95 
16.50 
45.42 
All of non-alcoholic ancestry 
28 
1333 
1060 
79.52 
55.94 
21.20 
34.72 
Differences 
•Alcoholic better = +1 
Alcoholic poorer = — j 
1 
256 
492 
26.78 
9.99 
+ 
4.70 
+ 
10.70 
+ 
From this table we note the following points: 
a. Considering the totals, and comparing chicks with any alcoholic 
ancestry, as a group, with chicks having no alcoholic ancestry, as a 
group, it is clear that there are fewer of the former than of the latter 
from a given number of eggs. In every 100 eggs from birds in the al- 
coholic series approximately 53 zygotes (embryos) were formed as against 
80 in every 100 eggs in the non-alcoholic series. 
h. The total number of offspring zygotes dealt with in the experi- 
ments (1628) is respectable, and such as to lead to reasonable con- 
fidence in the results, especially in view of the fact that these results 
are in every essential particular in full accord as to their sense with 
