al 
XXX1V 
organ consists of a transversely ribbed naked area on the 
underside of the fore-wing occupying the cell and extending 
to the submedian fold. The median vein bears a row of 
numerous transverse ridges, a corresponding “ file’ being 
found on the upperside of the hind tarsus. Stridulating 
organs of this or a similar type are known to occur in a number 
of species of Agaristidae and Noctuidae. In Musurgina the 
fore-wing has acquired an additional structure not observed 
elsewhere. The submedian fold which bounds the stridulation 
area posteriorly is replaced by a prominent, strongly chitinised, 
ridge, which might easily be mistaken for a true tubular vein. 
As the ridge does not extend distinct beyond the stridulation 
area, it is evident that the ridge has arisen in connection 
with and on account of the stridulating organ, as a support 
of the wing membrane. This stiffening might have been 
more economically effected by a tubular vein instead of a 
practically solid ridge. Evolution, however, is evidently 
unable to reconstruct the lost submedian tubular vein, although 
the trachea on which this vein is built up in generalised 
Lepidoptera (such as Zygaenidae, Cossidae, etc.) is still present 
in the chrysalids of the specialised families which have lost 
that vein. 
Musurgina recalls Pemphigostola Strand (1909), which is 
placed by the author with the Castniidae. On re-examination 
Pemphigostola will probably turn out also to be an Agaristid. 
Papers. 
The following papers were read : 
‘““ Notes on the Rhopalocera of the Dollman Collection,” by 
N. D. Ritey. 
‘““ The Male Genitalia of Merope tuber Newman (Mecoptera),” 
by Freperick Murr. 
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