44 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 95 



the two lateral thirds. The head is separated from the thorax by a 

 narrow but rather deep suture. Toward the head and prothorax the 

 sides of the mesothorax converge from the well-rounded basal wing 

 tubercles at an angle of about 30° with the middorsal line, the straight 

 converging portions of the sides of the mesothorax being about twice 

 as long as the outer profile of the prothoracic spiracle. 



When viewed from in front the head curiously suggests the head 

 of a manatee. 



The mesothorax is slightly broader than long, rather strongly and 

 evenly convex, and very slightly broader posteriorly than anteriorly. 

 The basal wing tubercles are low and broadly rounded. 



As viewed dorsally, the body increases in width from the posterior 

 end of the mesothorax to the third abdominal segment, then tapers at 

 about the same rate gradually and evenly to the base of the cremaster. 



The dorsal profile rises in a broad ellipse from the middle of the 

 anterior end to the row of tubercles between the prothorax and 

 mesothorax, then rises slowly in a broad curve to the end of the 

 anterior third of the mesothorax, whence it runs in an almost straight 

 line very slightly downward, descending somewhat abruptly near the 

 end of the mesothorax, which rises in a slight convexity. From the 

 end of the mesothorax the profile rises evenly and very slowly to the 

 third abdominal segment, and the fourth which is nearly as high, then 

 curves with increasing rapidity downward to the base of the 

 cremaster. 



From the middle of the anterior end the ventral profile curves in 

 an ellipse to the basal portion of the antennae, then runs in an almost 

 straight line to above the first abdominal segment, where it curves 

 broadly and, reaching the maximum height above the third abdominal 

 segment, descends in a more or less straight line to the base of the 

 cremaster. 



The prothoracic spiracles are large, auriculate with a protuberant 

 flaring posterior lip, and are directed forward and very slightly out- 

 ward. The outer side of the raised lip bears 12 to 14 broad, well-spaced 

 rounded ridges that run from the base to the swollen and somewhat 

 tubercular rim. Within the lip is a broad, dense band of short dark 

 brown hairs attached to a curved semicircular shelf of nearly uniform 

 width that leaves a large semicircular opening with a radius nearly or 

 quite equal to twice the width of the band of hairs. 



The position of the mandibles is indicated by a broad, low, rugose, 

 hairless hump. 



The maxillae reach very nearly to the tip of the wing covers. 



The tip of the antennae is 3 mm from the end of the wing covers. 



