24 E. B. Williamson and J. H. Willla.mson 



burners' creek, two and one-half miles east of town, attenuatus was found 

 not only on the same creek, but also on a creek crossed by the Rondon 

 Telegraph Trail, and on a creek two feet deep and three to eight feet 

 wide, with mud bottom and banks, flowing in a gully in the forest east of 

 town. It was taken on this mud bed stream on May 19 ; on the same date 

 minor was taken in the nearby jungle. At Manaos attenuatus, the only 

 species found there, was taken on a mixed gravel and clay bedded stream 

 in heavy forest beyond Flores. 



6. Perilestes kahli, new species 



Abdomen male 47-50, female 43 ; hind wing male 22-24, female 25 ; stigma 

 front wing male 1.10-1.15, female 1.20 ; stigma hind wing male 1.20, female 

 1.30 ; abdominal appendage male 1.30-1.40, female .35 ; male anterior lamina 

 from apex of sternum of segment 1 to apex of the posterior process 1.15- 

 1.20 ; female valve 1.90. 



Male. — Labium similar to that of solutus, the apical half or more of the 

 movable hook black; face similar to that of fragilis, but the black on the 

 apical part of the labrum is slightly produced basally in the median line 

 and on the lateral margins. 



Prothorax pale, only slightly darker above ; hind border flattened, above 

 straightened, slightly rising from either side to a little higher at the center, 

 the lateral extremities almost vertical. 



Thorax similar to that of fragilis with the black adjacent to the nar- 

 rowly brown middorsal. carina from about as wide as the antehumeral yel- 

 low stripe, (about two-fifths as wide as the reddish brown of the middle 

 area of the mesepistemum) to fully occupying the area from the pale carina 

 to the pale antehumeral stripe ; mes- and metinf raepisternum extensively 

 pale below and darker to black above to largely black with only the lower 

 triangular area pale. Metasternum as in fragilis but the lateral dark areas 

 may be the same or may be reduced and brown. Mesostigmal lamina low 

 and straight above, the lower third elevated into a low symmetrical triangle. 



Coxae pale, the third with or without the anterior face largely dark 

 to black. Femora pale, marked more extensively with dark than in fragilis 

 to such an extent in the case of the Bolivian male that the color pattern of 

 the first and second femora is obscured by the extensive black ; first femur 

 pale at base, the apical two-fifths to four-fifths of the dorsum brown or 

 black with or without a trace of a pale anteapical spot on the antero-dorsal 

 surface, black continued on the antero-ventral edge to near the base, dorsal 

 surface with trace of a brown postbasal area ; ventral surface pale, shading 

 to brown apically or the entire surface black; second femur pale at base 

 and black at apex with two brown areas between, each of which is more 

 extensive than the pale areas adjacent to it and nearly or quite encircles 

 the femur, the anteapical pale color, on the antero-dorsal surface, is pale 

 blue or green ; or the second femur is black with only a small pale postbasal 

 and a small pale anteapical area on the antero-dorsal surface ; third femur 

 similar to the pale form of the second described above, but the basal pale 



