Rau—O bservations on Samia Cecropia, Linn. 41 
VI. GENERAL CONSIDERATIONS AND CONCLUSIONS. 
(a) General Considerations. 
Only in a very few instances does Weismann give us 
any facts as to the duration of life of the male and 
female of any moth, and in those few instances the spe- 
cies is allied to the Cecropia moth. Since the moths are 
somewhat analogous, a comparison of Weismann’s facts 
with notes upon the Cecropia moth will not be out of 
order in a paper of this kind. 
In his essay on Life and Deatht Weismann says: 
‘‘Lepidoptera, such as the emperor-moths and lappet- 
moths, lay their eggs one after another and then die. 
We may certainly say that these insects die of exhaustion; 
their vital strength is used up in the last effort of laying 
eges, and in the case of the males, in the act of copula-- 
tion. Reproduction is here certainly the most apparent 
cause of death, but a more remote and deeper cause is 
to be found in the limitation of vital strength to the 
length and the necessary duties of the reproductive 
period. They live in a torpid condition for days or weeks 
until fertilization is aecomplished.”’ 
The emperor-moth as well as the Cecropia moth be- 
long to the family Saturniidae. Neither species in the 
imago state takes nourishment, still there seems to be 
some difference in the duration of life of the emperor- 
moth when compared with that of the Cecropia moth. 
The female Cecropia moth does not die after egg 
laying, and the males in the act of copulation, as Weis- 
mann tells us of the emperor moth; but the female 
Cecropias die, in the greater number of cases, before 
all the eggs are deposited, while the males live, on an, 
average of 9 days and 42 minutes, after separating from 
the females. 
The female Cecropias do not live in a torpid condition 
for days or weeks until fertilization is accomplished, but 
* Essays upon Heredity. English translation. 159. 1891. (2d Ed.) 
