126 My. G. C, Griffiths on the 
as the genus Mimas of Hiibner, which includes MW. tiliz 
and I. quercus, have the appliance fairly well developed. 
So also the very fine and remarkable South African moth, 
Lophostethus dwmolini, which is usually referred to the 
Smerinthinz, has the organ well and strongly developed 
in both sexes. 
The flight of many Smerinthinz is so different from 
that of the typical Sphingidz, and their habits are so 
much more sluggish, that it is interesting and instructive 
to find a diversity in the perfection of this apparatus. 
Further, as we shall presently see, the spina and retina- 
culum are absent in the Saturnias and Attaci, thus 
affording another character which strongly supports Prof. 
Poulton’s contention (Trans. Ent. Soc. Lond., 1888, p. 568) 
that the Smerinthi are closely connected with the Attaci 
in their natural affinities. 
In the Zygeenide the retinaculum, instead of being 
hook-like or ring-hke, resembles a long pocket upon the 
costal nervure into which the spina fits somewhat closely, 
the point being sometimes just visible at the extremity, 
but often quite concealed (Fig. 10). The genus Himan- 
topterus belonging to this group is however without the 
frenulum (Hampson—Moths of India, 1, p. 288). 
The Cossidee have the frenulum present but it is absent 
in the Arbelidz. 
The Lithosiide are possessed of the frenulum but in 
certain genera, Padenia, Garudinia and Pseudoblabes the 
costa of the forewing has a strong fold, holding tnat of the 
hindwing ; this fold is more largely developed in the male 
than in the female (Hampson, /. ¢. ii, pp. 97, 98). 
Both the Agaristidee and the Arctiidz have the process 
strongly and fully developed, the retinaculum in many of 
the latter being of very unusual length (Fig. 8). 
The Lymantriidz also possess the frenulum, with the 
exception of the genus Ratarda in which it is absent 
(Hampson, /.¢. 1, p. 493). 
In the Callidulidz one genus, Cleosivis, is quite without 
the frenulum, whilst in another genus, Herimba, the spina 
is long, the retinaculum of the male arising from the sub- 
costal nervure of the forewing. In the other genera of 
this family, Callidula and Pterodecta, the frenulum is 
present but minute; the retinaculum arises from below 
the median nervure (Hampson, J. c. 1, p. 322). 
In the Bombycide, Saturniidee and Lasiocampide a 
