234 long's second expedition. 



This species differs from the preceding in the following cha- 

 racters ; anterior portion of the hypostoma with a deeply trilobated 

 black spot; superior wing-scale rufous; a small yellowish spot 

 beneath the superior wing, and a yellowish line over the insertion 

 of the inferior wing ; a vertical, oblong, yellow spot each side 

 near the inferior tip of the metathorax ; a small spot each side 

 on the first segment of the tergum, and the yellow margin is re- 

 flected backwards on the lateral edge for a short distance ; the 

 spot of the second segment is elongated, and the bands of the 

 third and fourth segments pass round the venter. Size about 

 equal to the preceding, and seems to be allied to iho j>om2y'/unnis 

 Fabr. 



3. E. ANORMis. — Black; first abdominal segment very short 

 and dilated. 



Inhabits St. Peter's riv^r and Arkansa. 



% Antennae with the scapus yellow before ; hypostoma attenu- 

 ated, truncate at tip, with large, longitudinal punctures, and at 

 base a transverse, yellow, arcuated line, a [ 347] small spot on 

 the front, another in each emargination of the eyes, and a trans- 

 verse one behind the eyes on each side, yellow ; thorax densely 

 punctured, a yellow spot on each side of the collar ; wing-scale 

 yellow, with a pale-brown spot ; wings fuliginous ; scutel with a 

 transverse yellow line ; metathorax on each lateral margin with 

 an oblique yellow line ; pleura, a yellow spot under the superior 

 wing ; feet yellow; thighs, except at the knees, and spot on the an- 

 terior tibias, black ; tergum, segments yellow on their posterior 

 margins, first and second segments with each a yellow, lateral 

 spot, the former segment short, dilated, not pedunculiforiii ; ven- 

 ter immaculate. 



Length more than seven-twentieths of an inch. 



Excepting in the character drawn from the first segment of the 

 abdomen, this insect has a general similarity to the preceding 

 species, and the form of the anterior portion of the hypostoma 

 and the trophi, prove that this species is properly placed in this 

 genus. 



PTEROCHILUS Klug. 



P. 5-FASCiATUS. — Segments of the tergum yellow on their 

 posterior margins ; first and second segments with a lateral, fer- 

 ruginous spot on each. 



