DELTOIDES. 323 



essentially a southern species and has an extensive range 

 through Southern Europe, Syria, Armenia, Asia Minor, 

 Cyprus, Madeira, the Canaries, Egypt, Morocco, and Algiers, 

 and is very common in South Africa.] 



Genus 10. RIVULA. 



Antennae short, simple, thickly ciliated; palpi not very 

 long, triangularly tufted, porrected ; eyes naked, without 

 lashes ; thorax slender, smooth, with long shoulder-lappets ; 

 abdomen slender, smooth, tapering, not crested ; fore wings 

 small, bluntly triangular, very narrow at the base ; hind 

 wings proportionately rather large. 



We have but one species. 



1. R. sericealis, Scop.- -Expanse f to £ inch. Palpi 

 shortly triangular, body slender ; fore wings trigonate, straw 

 colour at the base, shading off to brownish-yellow behind ; 

 reniform stigma a black-brown spot; hind wings smoky- 

 white ; legs normal but long. 



Antennas of the male simple, thickly but softly ciliated, 

 light purple brown ; palpi not very long, triangularly tufted, 

 depressed, dull yellow ; eyes black ; head rather smooth, 

 white ; collar divided into two flaps, yellowish-white ; re- 

 mainder of the thorax narrow, smooth, dull yellow ; fascicles 

 pale yellow ; abdomen slender, tapering, smooth, yellowish- 

 white, with distinct lateral tufts ; anal tuft narrow and 

 pointed. Fore wings short and rather truncate, but triangular ; 

 costa very faintly arched ; apex bluntly angulated ; hind 

 margin beneath it straight and but little oblique, rounded off 

 however below the middle ; dorsal margin gracefully curved ; 

 colour soft dull yellow, palest at the base, tinged along 

 the hind margin with reddish-brown ; there is usually no 

 trace of transverse lines, but in some individuals these are 

 visible, slender, cloudy and much indented, the first some- 

 what perpendicular but broadly angulated, the second very 



