1925] Mystery of “Trilobite Larvce” Definitely Solved 139 
female. That they are not so scarce at the right place and at the 
right time is evidenced by the fact that my collectors managed 
to catch over a dozen specimens at the very same place, after I 
had found out the right way to expose the females. 
As full grown female-larvae can be collected in great num- 
bers, sometimes in hundreds within a shorter time than a week, 
and at almost any time of the year, it is only logical to conclude 
that males also must be developed fairly regularily, since par- 
thenogenesis does not seem to occur. That there is no standstill 
in the tropics is a well-known fact and it is indeed corroborated 
by the fact that larvae kept in captivity by me continuously 
developed into mature females the whole year round. 
It seems therefore probable that the males, guided by their 
senses, find their way directly to the hidden females and die on 
the spot immediately after copulation. This may be the ex- 
planation why they are so rare in nature and have so far escaped 
entomologists and collectors. The same obviously applies to 
the females which can be said to be still more scarce, as in no 
single instance has a mature female yet been found in the field. 
The life history of the imagines of both sexes is therefore still 
wrapped in mystery. 
The type of antennae and the general structure do not permit 
me to place the genus Duliticola within the family Drilidae, all 
known females of which are carnivorous. This applies also to 
the Drilid larvae known up to now, which are very different 
from the “trilobite larvae” in all more important features, while 
these latter undoubtedly remind one strongly of certain Lycid 
larvae, for instance, the larva of the genus Lyropaeus as described 
by Gravely. 
It is, however, a noteworthy fact that Duliticola and in all 
probability also the other genera of “trilobite-larvae” which 
undoubtedly soon will be discovered, differ strongly from the 
ordinary Lycids in following striking features: 
1. Neoteinic larviform females. 
2. No externally visible metamorphoses in the female sex. 
3. Female larvae reaching a gigantic size, with reduced 
mouthparts. 
