16 Transactions of the Society. 



Group 8. — Oncodes gibbosus L., one of a genus in the Oyrtidse, 

 is without any mouth-parts, the buccal aperture being completely 

 closed by a membrane ; an abortion of parts has taken place, more 

 complete than in Gastrophilus equi F., where remnants of palpi are 

 still to be found. The failure of the mouth-parts is not a constant 

 character in this family, the labium being long and much developed 

 in some species of the genus Cyrtus. 



Summary. 



1. A few remarks are made on some points of anatomy in 

 I'ii lex irritans L. bearing on its position in the Order. 



2. An anatomical character in the mouth-parts is noticed which 

 appears to divide the two great divisions in Diptera, the Orthor- 

 rapha from the Cyclorrapha. 



3. The " pharyngeal pump " in the head of Culex is figured, and 

 its homologues, found in the Tipulidse, Asilicke, Empidse, and 

 Dolichopodidse, are figured and described in several species. 



4. An atrophying fourth joint on the palpi of the female of 

 Culex annulipcs Mg. is figured and described. 



5. The trophi in the Leptidae, Lonchoptericla?, Dolichopodidse, 

 Phoridsp, and Conopod<e, are further discussed, and more species are 

 figured in all these families, except the Lonchopteridie and 

 Conopodse. 



6. The Platypezidse are placed in Group 2, and the trophi of 

 several species figured and described. The Psilidre are placed in 

 Group 6. 



7. The Lonchopterida) are transferred to Group 2. 



8. Mistakes in the homologies of the trophi of the Phoridre are 

 pointed out, and the species figured in 1904 is determined. Some 

 evidence is given as to the predaceous habit in this family. 



9. Two wrong determinations are pointed out in Group 5. 



10. Remarks are made on the trophi of the Pipunculidse and 

 their doubtful position and varying armature. 



11. Changes in the pharynx of some Muscidse are pointed out, 

 and the degeneration of the hypopharynx in some species 

 accounted for ; several dissections are figured. 



In conclusion I have to express my many obligations to 

 Mr. E. E. Austen, Lt.-Colonel Bingham,* Mr. J. J. F. X. King, 

 Dr. J. H. Wood and Lt.-Colonel Yerbury, not only for much kind 

 help in determination, but also for the provision of material for 

 dissection. 



* Since the above was written, Colonel Bingham, to the deep regret of all who 

 knew him, has gone to his rest. 



