1926 ] Strange way in which the Vishnu-M oth deposits her eggs 7 
odd egg is found at the top, representing a head. All are equally 
covered with short hairs and on every string - there are two 
longitudinal rows of dark spots along the outer margin. 
That the mother really has displayed a tendency to imitate 
the head of a caterpillar by placing one single egg on the top 
seems to be evidenced not only by the fact that in all strings 
there is an odd top egg but also that in strings no. 2, 5, 6, 7 and 
10 (from left) there are two top eggs, one on top of the other one, 
whereas at the lower end of each string there seems to be no 
marked tendency to place an odd egg (except no. 3). 
The longest egg string is no. 13 with 22 eggs. It is a strange 
fact that most of the other strings show two parallel rows of 7 
eggs in each with 1-2 single top eggs. 
In order to find out whether this peculiar way of depositing 
the eggs in the shape of larvae was only a queer habit in this in- 
dividual case or really a specific habit, I isolated six more fer- 
tilized females and awaited the result. In all cases the females 
laid their eggs in exactly the same way. Two of the females 
under observation were kept in very large cases, but the eggs 
were found to be laid in a strikingly singular way. One or two 
top eggs were always to be seen and the same arrangement with 
the dark spots forming two longitudinal lines was also observed . 
We may therefore safely conclude that this peculiar way of 
depositing the eggs in larva-like shape is a characteristic of 
Trabala vishnu. 
The advantage of this form of “mimicry,” if we may use 
this term, is obvious. It is a well-known fact that hairy cater- 
pillars are distasteful and discarded by most birds, the insects’ 
greatest enemies. Only the cuckoos seem to form an exception 
to the rule. Undoubtedly the eggs laid in this way are better 
protected than if laid separately or in disorderly heaps as is the 
case with most Lasiocampids, and it seems to be fairly clear that 
the mother in this case by making the unprotected earliest state 
of the development so strangely similar to hairy distasteful larvae, 
has solved the problem of protecting her offspring ab ovo in a more 
effective way. 
