ICO 



The Fly of Chirononms 



a median suture ; this appears to represent a pair of dorsal 

 sclerites. 

 Thorav. A median section througli tlie thorax shows plainly the 



limits of the segments upon 

 the ventral surface, but on 

 the sides the boundaries can 

 only be traced with difficulty 

 until the clue is discovered ^ 

 Upon the mid-ventral sur- 

 face the protliorax is of 

 moderate extent, the meso- 

 thorax very large, the meta- 

 tliorax short, and defined by 

 two apodemes for muscular 

 attachment, the medifurca 

 and postfurca (tig. 70). Such 

 apodemes are common in 



Fig. 70. — Ventral view of part of 

 thorax of fly, with the attachments 

 of intermediate and hind legs. &i, 

 mesosternnm. <, trochanter of in- 

 termediate leg. f, ./; trochanter and 

 femur of hind leg. a, abdomen. The 

 medifiirea and postfurca are seen in 

 the middle line. 



Fig. 71. — Nearly median section of fly, showing the longitudinal 

 niesothoracic muscles above, and the vertical ones below, .ff, (/', f/", 

 pro-, meso-, and metathoracic ganglia, il, intermediate leg. lil, 

 hind-leg. 



' Note by A. Hammond. In my paper on the thorax of the blow-fly 

 {Journal Linn. Sue. Zool., vol. xv, 1881, pp. 9-31) I determined the whole of 



