64 THE EARLY STAGES OF TABANID^ 



first protuberances of infralateral series. Each segment from fourth to tenth 

 has a pair of impressed dots on inner pair of elevations of the posterior longitu- 

 dinally striate ridge. Segments six to nine have four of these impressions, one 

 outside of each of the median pair." 



"On the last or eleventh segment the anus is a semicircle with the convex side 

 downward, overhung by four prominent tubercles in bilaterally symmetrical 

 pairs. Mouth of the air tube a smooth oval surface just above the anal tubercles. 

 It has a vertical slit and is surrounded by a projecting crenulate frill." 



Pupa (Plate 11, Fig. 121, a, b, c). — One of the full grown larvae 

 collected by Mr. Pergande pupated and a female imago issued May 

 29, 1899. McAtee's description follows. 



"Length of the pupal shell 19 mm. ; greatest diameter 6.5 mm. Head and thorax 

 of the pupa a hghter, abdomen a darker ferruginous. Head and thorax finely 

 and irregularly wrinkled; anterior half of each abdominal segment finely wrinkled 

 transversely, posterior half with wrinkles less distinct or absent (especially on 

 ventral surface), but very finely and closely punctuate. This makes the color 

 appear more intense, in places almost orange. Middle of the segments, except 

 the first, surrounded by an interrupted fringe of definitely grouped sharp pointed 

 spines, the larger of which tend to be serrate." 



"Vertex of head marked by a narrow rounded longitudinally wrinkled trans- 

 verse ridge. In the depression between this ridge and the antennal prominences 

 and in front of the extremities of the ridge are two outwardly directed setae. 

 Antennal sheaths short, appressed, downwardly curved, conical, arising from 

 two low wrinkly protuberances (the antennal prominences above mentioned). 

 These prominences separated by a deep fold, and from them curved and diverg- 

 ing impressed lines run down the face. Below each antennal sheath is a widely 

 separated vertical pair of setae." 



"Prothorax longitudinally wrinkled, except for a smooth area behind and 

 below each antennal sheath. A setiferous tubercle stands above each of these 

 smooth areas. Prothorax angulate in the median line behind. Mesothorax 

 three times as long as the prothorax, bearing two spiracular tubercles near an- 

 terior lateral angles (about opposite the middle of each lateral half of the pro- 

 thorax). These tubercles similar to those described below, but compUcated by 

 flexures of the walls. They bear at the summit upwardly arched crescent- 

 shaped rimae or air slits. The only setae I can find on the mesothorax are one on 

 each side directly back of these spiracular tubercles. Metathorax very short in 

 the median line, but somewhat longer at the sides, which have two rounded angles 

 anteriorly. Wing pads and leg sheaths, the latter slightly the longer, almost 

 covering ventral surface of the first abdominal segment." 



"Middle of each side of first to seventh abdominal segments with elevated 

 round polished knobs bearing on the posterior portion of their summits the pos- 



