Explanation of Plate VII, 



namber of .sen<5ory hairs on the ed^e. The under-sides of the labella 

 are partly chitiniscd, and similar conditions exist in P. cpncinna ; it 

 is indicated on both figures by the darker shading. 



The rod at the base is one of the mandibles which are in this 

 species separate, but embedded on the ventral side. The mentum 

 is but little developed, but in the Leptid genus Ghrysopilus it will 

 be found in a condition very similar to those figured as 11, 12, 15, 

 with the median suture and the cleft process at the anterior end 

 Length li'^s mm. or Jy inch. 



Fig. 9. One of the labella of Phora concinna, Mg. ^ , to show the 

 trachea} springing from a plate, and the great number of "taste 

 hairs" on the edge. The triangular process at the side is the 

 aculeation characteristic of the Phorid trophi. It consists of the 

 lacinia? of the maxilla} fused at their points. In Gymnophora 

 arcuata, Mg. and P. cumne?ins, Beck. ( $ only) the stipites and 

 cardines are also visible at this part of the mouth. Length t g mm. 

 or tV inch. 



Fig. 10. The labial palpus of P. concitina. To show the two 

 joints, a Nematocerous character never found in the MuscidjB. 

 Length } mm. or t^ inch. 



Fig. 11. Mentum of L. fiavicauda., dissected out from the mouth and 

 viewed from the ventral side, the anterior portion being uppermost. 

 To show the median suture of the jjart, absent in the Muscidae. 

 (Compare Fig. 13.) 



The bristles are also of interest, being exactly similarly placed 

 in P.curvinervis, Beck. ,^ . (Compare with Fig. 15.) Length f mm. 

 or rhs inch. 



Fig. 12. Labium of Dolichopns griseipeniiis, Stan. Ventral side, 

 to show the mentum, witli the median process and the bristle-holes. 

 (Compare with Figs. 11 and 15.) Breadth, circa f mm. or ^V i»ch. 



Fig. 13. Mentum of Musca corvhia, F. Shown in the same posi- 

 tion as the other figures of this part. On comparison with them it 

 will be seen that the median suture is wanting ; this condition is 

 always found in the Muscidse. Length at longest part y\ mm. or 

 ^V inch. 



Fig. 14. Tlie characteristic Phorid bristle: for comparison with 

 Fig. 16. Taken from the middle tibia of P. incrassata, Mg. 9 • 

 Length ^ mm. or yi, inch. 



Fig. 15. Mentum of P. curviiiervis, Beck., for comparison with 

 the part in other families. The sides are much developed and Hap 

 over ; this is indicated in the drawing. Length -^^ mm. or ij-J^ inch. 



Fig. 16. Mycetophilid bristle, one of two on the apex of the hind 

 tibia of Sciara thomx, L. This structure is found only on the legs 

 of the MycetophilidsB, Length A mm. or o'^ inch. 



