FAMILY TIPULID.E — THE CRANE FLIES 39 



EXPLANATION OF PLATE 



1. Tanyptera fumipennis, venation. 



2. Dicranota (Plectromyia) modesta, venation. 



3-10. A series of diagrams to illustrate the modification of the outer subcostal 

 and radial fields of the wing-, as found in the Tipulinse, Cylindroto- 

 minje, Lechriini and Limoniini. 



3. The type found in the Orimargaria: Scs preserved, R1+2 complete, at- 



taining the wing-margin. 



4. A further development of 3. . Sc'. has moved distad, shortening Ri; Ri^o 



still entire. 



5. Condition as in 4 but with tip of Ri+2 atrophied. Found in several Ori- 



margaria, Limoniaria. 



6. An accentuation of 5. The atrophy of R,+: is still greater, R, more 



shortened and more or less in transverse alignment with the fi'ee tip 

 of Sc;. Condition found in numerous Limoniaria. 



7. A still further modification of 5. The atrophy of R1+2 is now complete 



and Ri is in direct transverse alignment with R^, both in turn being 

 in transverse alignment with the free tip of Sc;. This is the com- 

 monest type in the Limoniaria, being found in most members of the 

 following subgenera of Limonia, — Dicranomyia, Geranomyia and 

 Rhipidia, as well as in some Limonia, s.s. 



8. A type that reverts back to condition 5, with a long spur of R1+2 persist- 



ing, with the free tip of Sc2 migrated distad along this spur to lie 

 beyond the level of R2. A condition found in several subgenera of 

 Limonia, as Peripheroptera, Limonia and Libnotes. 



9. A further modification of 8, where Sc2 has migrated to the extreme tip 



of the spur of Ri+i but still forms a rectangular bend. Limonia: 

 Libnotes. 



10. The culmination of the series, where the free tip of Sca has migrated to 

 the extreme tip of the spur of Rn2 and then bends to the costal margin 

 at a gently oblique angle. This condition is common in many Limonia 

 of the subgenera Limonia and Discobola. 



EXPLANATION OF SYMBOLS 

 Comstock-Needham system, as modified by Alexander and Tillyard 



C = Costa; Cu = Cubitus; 1st M2 = cell 1st M^; M = Media; m-cu = me- 

 dial-cubital crossvein; R = Radius; r-m = radial-medial crossvein; Rs^ Radial 

 sector; s =: supernumerary crossvein; Sc = Subcosta; A = Anal veins. 



