Frenulum of the Lepidoptera. 129 
to slight pressure. The spina of the female rests 
under a catch composed of scales proceeding from the 
costal nervure of the forewing, which bends over very 
strongly. It is to this catch that Prof. Comstock probably 
refers when he goes on to remark :—“The females also 
possess a frenulum-hook; but this is not so highly 
specialised as that of the male.” It may be mentioned 
that Sesia omphale, 2, a native of Florida, has a weak 
double spina, and that Z'rochiliwm erabroniforme, 2, has a 
frenulum composed of five spinulz locking into . scales 
upon the median nervure, as in the normal development 
of this appliance. 
The Tortricina and the majority of the Pyralidina have 
the frenulum of the usual character, but it is in some of 
the members of the latter group that the most singular 
variations of this organ exist. Hitherto we have found 
that the spina of the male insect works through a retina- 
culum arising from the costal nervure of the forewing : 
but in several species of our british Pyralides the male 
spina locks into a fasciculus of strong scales on the median 
nervure of the wing, in fact in the manner generally 
characteristic of the organ in the female. Amongst these 
.species are Agrotera nemoralis, Endotricha flammealis, 
Diasemia literalis, Stenia punctalis, Botys flavalis, B. 
Juscalis, B. verticalis and B. asinalis. In each of these 
species the female insect has two spinule, but in Cata- 
clysta lemnalis (Fig. 16) which has the male frenulum as 
above described, the female has a single spina exactly 
similar to that of the male. In the subfamily Phycitine 
according to Ragonot (Mon. Phyc: 1894) and Hampson 
(Moths of India, iv, p. 64) the spina of the frenulum is 
simple in the female, asin the male. A striking peculiarity 
of the Chrysauginee is referred to by Ragonot (Essai sur 
la Classn. des Pyralites, 1891) and Hampson (P.Z.S. 1897, 
p. 633). In many species the spina of the male is 
described as being much thickened, flattened and con- 
torted, and in some instances accompanied by a strong 
lower fork; this very singular development does not 
appear to have its parallel in any other group. 
Certain species of the genus Crocidolomia referred to by 
Hampson (Moths of India, iv, p. 371) have a thick tuft of 
hair springing from the subcostal nervure, whilst from a 
fringe below the median nervure arise four strong curved 
spines playing on the subcostal tuft. At first sight these 
