130 Mr. G. C. Griffiths on the 
processes appear to be ancillary to the frenulum, but a 
careful examination by the writer of several specimens 
from Queensland, leads to the conclusion that this is not 
the case. No binding of the wings can be due to these 
spines, as both they and the tuft of hair belong to the 
forewing only, whilst the supposition that they hold down 
the point of the spina after passing through the retina- 
culum is negatived by the fact that they are at too great 
a distance from the base of the wing to come in contact 
with it. 
The great division of the Tineina, which has been 
observed by several recent writers to be of a very hetero- 
geneous character, proves to be so also in respect to the 
frenulum. Whilst the great majority of the species pos- 
sess 1t and in numerous instances the spina is of a greater 
size In proportion to that of the insect than in many of 
the larger moths, yet in one or two groups it is found to 
be wanting. In the Nepticulide, particularly, this is the 
case ; also in Micropteryx, which in most of its species has 
a well-developed jugum, this is only rudimentary however 
in M. calthella and M. seppella. Several species of this 
group have a few strong hairs on the costal margin of the 
hindwing, which, as Dr. Chapman points out, may be a 
commencing frenulum. 
Turning next to the structure of the organ under con- 
sideration we find on microscopic examination that the 
spina of the male insect, simple and homogeneous as it 
appears at first sight, is really composite in its character. 
Viewed under a high power its apparently polished and 
smooth surface is seen to be deeply furrowed with fine 
longitudinal lines,'and the significance of this is made 
clear when, on making a transverse section, we find that 
the spina is really an agglutination of tapering hollow 
tubes or hairs, and is in fact evolved from the less perfect 
organ of the females by fusion of the bunch of spinule 
into one strong bristle. Being thus made up of hollow tubes 
the spina possesses great elasticity as well as strength. 
The spinule of the female when microscopically ex- 
amined are found to be simple hollow tubes, and these, 
with the few exceptions just cited, vary in number from 
two in some species, to upwards of twenty in others. 
They spring lke the spina of the male from a raised 
socket formed by an extension of the costal nervure of 
the hindwing. 
