PERLA. 25 



Yellow varied with fuscous ; head as wide as prothorax, yel- 

 low, disk brownish-black, only two ocelli ; antennae fuscous ; pro- 

 thorax yellow, rugulose, externally the half each side fuscous, 

 sulcus upon the middle fuscous ; posteriorly narrower, in front and 

 sides rounded, anterior angles subacute, posterior ones rounded ; 

 feet yellow, knees, tibiae and tarsi externally fuscous ; abdomen 

 yellow ; setae yellow ; J" last ventral segment large, ovate ; wings 

 fusco-subhyaline, costal margin somewhat yellowish, veins testa- 

 ceous. (Male.) 



Length to tip of wings 18 ( 22) millim. Alar expanse 33 

 (41) millim. 



Hob. Mexico (Koppe); Cordova (Saussure). 



22. P. dilaticollis! 



Perla dilaticollis Burm.! II, 880, 7. Pict.l Perl. 240, 36 ; tab. xxiii, fig. 

 510. Walk. Catal. 158, 58. 



Yellow varied with brown ; head wide as the prothorax, yellow, 

 in front clouded with fulvous : ocelli only two, black ; the antennae 

 brown, the base luteous ; prothorax narrower behind, anteriorly 

 rounded, rugulose, brown, a broad, yellowish middle vitta, sides 

 oblique, anterior angles rounded ; feet yellowish, knees and tibiae 

 externally a little infuscated ; abdomen and setae yellowish ; < last 

 ventral segment large, ovate ; 5 antepenultimate ventral segment 

 truncate ? wings testaceo-subhyaline, veins testaceous, accessory 

 subcostal vein incurved. 



Length to tip of wings 10 13 millim. Alar expanse 20 27 

 millim. 



Hob. Mexico ; Columbia ; Brazil ; North America (Museum 

 Vienna). I have not seen the Mexican specimens. 



23. P. litura. 



Perla litura Pict. Perl. 242, 37; tab. xxiv, fig. 13. Walk. Catal. 

 159, 59. 



Yellow varied with brown ; head as wide as the prothorax, brown, 

 margined with black, only two ocelli, antennas blackish ; prothorax 

 brown, rugulose, a broad middle yellow stripe ; broad, narrower 

 behind, in front rounded, anterior angles rounded, sides oblique ; 

 feet yellowish, knees, tibiae externally and apical ring, and tarsi 

 fuscous ; abdomen and setae yellow ; wings grayish-subhyaline, 

 costal margin obscurer, veins fuscous. (Taken from the figure and 

 description of Pictet.) 



