CONSTITUTION AND DEVELOPMENT OF TERMITES. 269 
just as a blind man does his stick, as Lespés observes. But 
they are not accustomed to use them in mutual caresses, like 
other social insects. If the antennz are cut off at the base 
the insect becomes inert, stands in a fixed attitude, almost dis- 
regards the difference between light and darkness, quivers (vide 
infra) at rare intervals, and then for a shorter period and less 
violently than usual. It is not successful in soliciting excre- 
ment (vide infra), or does not directly attempt to do so. All 
these inconveniences are only partially exhibited if the an- 
tenne are detached more or less remotely from their base.] 
Fritz Miiller’s observation! that the number of antennal 
joints in Calotermes rugosus is increased by the successive 
formation of new joints at the base of the third is well known, 
and has led to the division of the antenna into two components 
(base and flagellum), as in other Arthropoda. 
I have attempted to determine the origin of the new joints 
in Calotermes flavicollis, but have not been successful in 
obtaining a clear idea of the process. 
In deciding whether any given joint is the most recent, its 
smallness, its freedom from hairs, and the indistinctness of 
the line of demarcation between it and the parent joint must 
be taken into account. But it will be readily understood that 
all these criteria are apt to fail. 
In the present case, the one which appears most practicable 
(the presence or absence of hairs) may certainly lead us 
astray. In fact, antenne of 13, 14, 15, 16, and 17 joints, with 
the third and fourth joints glabrous, are to be found, as well 
as completely pilose antenne of twelve to sixteen joints (fig. 
22). The natural inference is that the third or fourth joint, 
which was pilose in the latter examples, has become denuded 
in the former (e.g. for an antenna of fourteen joints, the 3rd 
and 4th pilose, to become fifteen-jointed (fig. 21) with the 3rd 
and 4th hairless, one or other of the latter joints must neces- 
sarily have lost its clothing) ; this may have taken place in 
connection with ecdysis, as we shall see later. 
1 [* Jen. Zeitschr.,’ ix, pp. 246, 247.] 
