26 



W. WESCHE — THE LARVAL AND 



There are single hairs on the abdomen, and phimes o£ branched hairs on 

 the seventh segment which are longer in a more mature pupa. The anal 

 plates are subcircular with fine dark short hairs on the lower edges. 



Greatest length of thorax 1^-2 mm. 



Described from four larva? and five pnpa?. 



[Larvse found in a small quantity of water in an empty fish-tin upon the 

 dust-heap behind the kitchen. — W. M. G.] 



Siphon and anal segment of Stefjomyia fasciuta, F. 



Fif^. 1. Lateral view of the parts : a, bowel ; it will be noticed that the view of the comb is 

 obscured, though the remaining scales are above the bowel ; they are eight or nine 

 in number. The structures are those seen with a magnification of about 60 

 diameters ; the animal, quite unprepared for microscopic examination, lyi^o ^^^ ^ 

 trough of formalin, or in water. The long hairs on the ventral side of the anal 

 segment have been curtailed by the exigencies of space ; they are as long as those 

 on the dorsal edge. The ventral beard has been denuded, and is drawn as it exists 

 on the specimen. 



2. The same siphon reversed showing the abnormal condition of the spines on the left 



side. 



3. The three lowest spines on the left side drawn larger, though seen with the same 



magnification. 



4. A scale of the comb drawn larger but seen with the same magnification as fig. 1. 



Goeldi figures more teeth on the part, but these obviously require much more 

 magnification for resolution. 



