224 K. E. SNODGRASS. 



The apical appendages are simple (fig. 137). The dorsal one (A) 

 is large and mostly conceals the others in a lateral view (fig. 138). 

 The middle one (B) is densely chitinous and ends in a flat point. A 

 lateral lobe projects over the outer edge from below. The lower 

 appendage (C) is large, thick, fleshy and united basaily with the 

 second. 



The apodemes of the central vesicle (fig. 133, ap.) are unusually 

 long, being greatly larger than the anterior arms of the vesicle. The 

 guard of the penis is a long, pointed, stylet-like structure, swollen 

 at the base, grooved above. It arises from the floor of the genital 

 chamber just above the bases of the long slender processes (a) that 

 project from the edge of the sternum. The penis curves imme- 

 diately downward from the central vesicle. In the specimen from 

 which figure 138 was drawn it was projecting posteriorly from the 



hypopygium. 



The anal tube has the usual form. A minute, chitinous tendon 

 runs along its upper edge from the roof of the genital chamber. 



Tipula illustris Doane (PI. XII. figs. 61, 62, 63, 67). 



The abdomen and hypopygium of this species have a very simple 

 form externally. The eighth segment is cylindrical, with the ster- 

 num prolonged beneath the ninth. 



The hypopygium is a simple cup set vertically upon the eighth 

 segment, and may be mostly retracted within this segment. A longi- 

 tudinal (vertical) suture on each side separates the tergum from the 

 sternum (fig. 61). The sternum is continuous across the ventral 

 aspect of the segment without any constriction (fig. 63). The pleura 

 are fused with the sternum, and there are no pleural sutures. 



There are only two apical appendages on each side. The first 

 (figs. 61 and 62, A) is a conspicuous strap-like lobe rising vertically 

 from the rim of the genital chamber but bent inward distally. The 

 second appendage (fig. 62, B) is a wide irregularly triangular lobe 

 with the two distal angles prolonged each into a long tapering horn- 

 like process. This appendage is mostly concealed mesad of the first 

 and within the genital chamber. 



The penis and central vesicle have the ordinary form. The arms 

 of the latter are rather short. The penis curves forward only into 

 the posterior part of the eighth segment. The guard of the penis 

 (fig. 67) has a wide, thick body which laterally bears two sharp 

 lobes, and is mesially prolonged posteriorly into a slender tapering 



