i30 
GENETIC STUDIES ON THE SILKWORM 
be regarded as the parental characters recapitulated in the course of onto- 
genetic development. A given character is not only transmissible, but so 
precisely transmissible as to reappear in a stage or stages proper to it. 
The figures put as the suffix to each lot number indicate in the present 
paper, the year of rearing, in contrast to those in my papers published until 
1914, which refer to the year of egg-deposition. 
The formulae ABab, AbaB, AaBb and A-B- arc used in different senses ; 
ABab and AbaB stand for the hybrids derived from the gametes AB x ab and 
Ab x aB respectively, while AaBb represents either sort of these hybrids. 
A-B- indicates any zygote that involves at least one dose of both A and B. 
The symbols of hereditary factors concerned in the present work are as 
follows : 
5, striped marking, J) 
M, moricaud marking, 
P, plain or non-marked, 
Q, quail marking, 21 
PQ, normal marking, 
Z, zebra marking, 
L, multilunar marking, 
K» knobbed skin, 
0, opaque skin, 
B, melanic, 
T, 3-moulting, 
Y, yellow cocoon, 
6, green cocoon, 
s. absence of S ; 
m, absence of M ; 
p, absence of P ; 
q, absence of Q ; 
pq, pale-quail marking ; 
z, absence of Z ; 
1, absence of L ; 
k, smooth ; 
0, transparent or "oily" ; 
b, chocolate ; 
t, 4— moulting ; 
y, absence of Y ; 
jg, white cocoon. 
The silkworms in my experiments were reared entirely in the College 
nursery up to 191 3 ; in the summer of 1 9 1 3 and the spring of I9i4they were 
partly reared in the Sericultural Institute of Hokkaido, while the culture in 
1) This ''striped" must be distinguished from the "striped" of Toyama, which I prefer to 
designate as "zebra", the term first adopted by Cohtagne and later often employed by Toyama 
himself. 
2) This name is substituted for the "Kasuri" of my 1914a paper. 
