Heterocerafrom Costa Rica. 175 



Mesothen montana, sp. n. 



Antennae black. Head, collar, and thorax dark brown. 

 Abdomen yellow ; two rows of black dorsal spots on seg- 

 ments 2-6. Thorax below dark brown. Legs yellow ; tarsi 

 and part of hind tibiee dark brown. Wings hyaline ; the 

 veins and margins narrowly dark brown, widening at apices ; 

 the discocellnlar of fore wings broadly blackish brown. 



Expanse 39 mm. 



Hah. Volcano Poas, 7000 ft. 



Afesot/ien ethela, sp. n. 



Palpi brown. Head black ; frons white ; small white 

 spots behind antennse. Collar and thorax dark brown, 

 patngia black; large white spots on shoulders. Abdomen 

 bright yellow, terminally black. Fore legs brown, cox^ 

 white ; hind legs outwardly black, inwardly buff. Wings 

 hyaline, the veins and margins brown. Fore wings : apex 

 and tornus more broadly brown, a small white spot at base 

 of subcostal vein. 



Expanse 28 mm. 



Bab. Sixola. 



Chrostosoma sitiona, sp. n. 



Palpi, antennae, and head black. Body yellow, the abdo- 

 men terminally black. Legs black, cox» yellow. Wings 

 hyaline ; veins and inner margins finely black ; apices very 

 broadly black. Fore wings : the costal and outer margin 

 rather broadly black ; some yellow at base. 



Expanse 29 mm. 



IJab. El Sitio. 



Cosmosoma nohilis, sp. n. 



Antenna, palpi, and head black; the frons metallic blue. 

 Collar black with metallic-blue spots. Thorax black ; some 

 dorsal blue scales ; a large opalescent blue spot on meta- 

 thorax. Abdomen black ; the segments posteriorly narrowly 

 yellow ; lateral transverse blue lines and sublateral blue spot ; 

 the last two segments metallic blue ; two opalescent spots 

 dorsally on first segment. Legs black irrorated with blue. 

 The wings hyaline ; veins and margins black, broadly at 

 apices. Fore wings : a large black spot at end of cell; the 

 base of costal margin and below cell with metallic-blue 

 scales. Fore wings below : the basal thir*J of costa streaked 



