93 



13. Hind wings with basal spot obsolete ... ... ... leucacma 



Hind wings with basal spot well developed ... ... antithefa 



paraula 



anepsia 



macroplaca 



14. Antennae with apex white ... ... ... ... 15 



Antennae wholly black .. .. ... ... 16 



15. Spots small, opaque, deep orange ... ... ... phepsalotis 



Spots moderate, semitransparent ... .. ... annulata 



16. Abdomen hairy ... ... ... .. ... 17 



Abdomen smooth-scaled ... ... ... ... 18 



17. Thorax with yellowish markings ... ... ... recedens 



Thorax wholly black ... ... ... ... orphnoa 



18. Patagia orange ... ... ... ... .. humeralis 



Patagia black ... ... ... ... ... 19 



19. Distal spot of hind wings triangular, touching basal spot 



on median vein ... ... ... ... ... trigonophora 



Distal spot of hind wings roundish ... ... ... aperta 



Hydrusa xanthosoma, n. sp. 



Male, 25-28 mm. Antennal pectinations vp-ell marked, l^. 

 Veins 3 and 5 of hindwings closely approximated at base. 



Head and face orange. Antennae fuscous, irrorated dorsally 

 with orange scales. Thorax orange. Abdomen orange without 

 black markings, tuft orange with a few lateral fuscous hairs. 

 Legs orange, anterior and middle tarsi fuscous. Forewings 

 blackish, with confluent orange spots ; first spot, small, roundish ; 

 second, wedge-shaped ; an additional orange streak separated by 

 blackish vein from second spot, and by a narrow black line from 

 costa ; third, elongate prolonged upwards and inwards, separated 

 from second only by median vein ; fourth, elongate, surmounted 

 by an additional spot ; fifth, bisected by a black vein into two 

 equal elongate segments ; an elongate connecting spot developed 

 between fourth and fifth ; and another between fifth and third ; 

 these confluent spots leave two small black areas, first beyond 

 second spot, sometimes confluent with costal and anal black 

 areas ; second separating first and third spots. Hindwings 

 orange, hindmargin broadly but irregularly blackish, a small 

 black dot below middle of costa. 



Varieties. — The extent of orange suffusion relatively to black 

 ground color varies. The connecting spot between fourth and 

 fifth, usually well developed, may be completely absent. 



A very distinct species, remarkable for the , absence of black 

 rings on abdomen, and the unusually developed confluent orange 

 markings on wings. 



Barrier Range, North- West Australia ; some half-dozen 

 specimens, all males (Coll. Macleay), one of which is now in my 

 collection. 



