350 MEDICAL ENTOMOLOGY 



is similar to that of Musca dottiest ica, but with a long delicate appendage 

 (spine) at the narrow end. Each egg is laid singly in cow dung with the 

 spine, which in the mature egg is almost black in colour, directed upwards. 

 Length of egg 1*8 to 2 mm. ; length of spine 1 mm. The larva is of a 

 yellowish white colour with a slight lemon tint when mature ; anterior 

 spiracles with five papillae. The piiparium is of a characteristic greyish 

 white colour ; the larva, contrary to the habit of the other species of this 

 group so far as they are known, does not leave the dung to pupate ; 

 the puparia can only be recovered by breaking up the dung. 



This species of Musca is abundant in Madras throughout the year, 

 and according to Annandale it is also common in parts of Bengal. 

 Its breeding habits are peculiar in that it only lays its eggs in cow dung 

 where it is collected in heaps ; it has never been seen to lay its eggs in 

 small patches of dung in the field. It is not uncommon to see as many 

 as eight females each depositing an egg in the same spot. The flies, for 

 both sexes behave in the same way, are only seen on cattle and horses. 



Musca gibsoni, Patton and Cragg. Male, Ground colour of thorax 

 slate grey to dark grey with four broad longitudinal black stripes ; in 

 most of the specimens the stripes cannot be easily seen, as the whole 

 thorax appears bronze black. Abdomen reddish brown with shimmering 

 white bands. First segment black except for two horizontal yellowish 

 brown bands at the lower border. Second segment with a broad black 

 median longitudinal stripe, broad at the upper end and narrow towards 

 the lower, on each side of which there is a narrow shimmering yellowish 

 grey stripe ; the remainder of the segment is reddish brown with a white 

 patch at the lateral edge. Third segment with a narrow black median 

 longitudinal band and a larger white patch at the edge, the markings 

 otherwise similar to those of the second segment. The lower border 

 of the third segment with a dark brown patch which forms a con- 

 spicuous spot. The fourth segment is dark grey to olive grey with a 

 narrow white stripe at each side, and a lateral clove brown band. 

 Length 5'5 to 7 mm. 



Female. Thorax, yellowish with four longitudinal black stripes. Ab- 

 domen reddish yellow ; first segment with a dark transverse band at 

 the lower border as in the male. Second segment with a dark median 

 longitudianl band narrower than that on the male ; a broad yellowish 

 grey shimmering patch at each side, and a lateral brown band. Third 

 segment markings similar to those of the second, but all the bands 

 are narrower. Fourth segment, centre olive grey, with two narrow lateral 

 clove brown bands. Length 6 to 8 mm. 



