F. R. COLE 39 



PTERODONTIA 



Pterodoniia Gray in Griffith, Animal Kingdom, xv, p. 770, pi. cxxvii, f. 3, 



(1832). 



The eyes occupy most of the head, which is small in proportion 

 to the thorax. The face is small and on the extreme lower part 

 of the head, the antennae being placed in its upper part. The 

 back of the head is not inflated ; the eyes are holoptic and thickly 

 pilose. There are three ocelli on the small vertical protuberance. 

 The antennae are short, three-jointed and close together at the 

 base; the first joint is cylindrical, the second rounded, and the 

 third varying in shape and smaller than the other joints. 



The thorax is large and swollen and with more or less thick, 

 erect pile. The humeral calli are not very large, but the post-alar 

 and pf'aealar callosities are of good size. There are no bristles 

 or very long hairs on the body. The scutellum is of medium size 

 and rather short, with a deep rounded margin so that only a small 

 portion has a flat surface. 



The abdomen is large and inflated, appearing round from 

 above. The squamae are quite large and with short hair on the 

 surface. The genitalia are retracted and the structure hard to 

 make out. The tibiae are armed with apical spurs, or sharp 

 projections, a small inner one (in species I have examined) and a 

 stronger outer one. The legs are rather slender for the size of the 

 insect. 



The wings have a peculiar thickening of the costa, which in the 

 male sex bears a spur or tooth; the females apparently lack this 

 tooth. The second longitudinal vein curves up into an enlarge- 

 ment of the costa. P. analis shows the presence of two discal 

 cross-veins. The outer first basal cell has merged into the discal 

 cell. The lower branch of the fourth vein bends sharply down- 

 wards and meets the short upper branch of the fifth, then goes to 

 the wing margin. In P. virmoridn, according to \^errall, the outer 

 discal cross-vein and upper veinlet from the discal cell have dis- 

 appeared and there is apparently no upper branch to the fifth 

 vein. This is also true of P. flavipes. P. analis has three pos- 

 terior cells and P. Jlavipes, two. P. johnsoni new species appar- 

 ently is a connecting link between these two types of venation ; the 

 outer discal cross-vein being suggested, but the upper veinlet 

 from the discal cell has disappeared. 



TRANS. AM. ENT. SOC, XLV. 



