PARASITES AFFECTING THE SKIN 49 
believed to transmit the Trypanosoma Theileri, which 
causes the so-called biliary fever of cattle. 
(2) Melophagus Ovinus (Sheep-Ked).—This insect is 
without wings, and much resembles a louse. It lives 
in the wool of sheep, and finds its nourishment in the 
grease, scurf, and droplets of exuded blood. 
It is greyish-brown in colour, with a small narrow 
thorax and a large oval abdomen. Length, 3 to 5 milli- 
“metres. 
Muscide.—Some of the Muscide exist on the skin 
while in the larval state. 
Sarcophaga Magnifica is a greyish fly, 10 to 30 milli- 
metres in length.. It is viviparous, and deposits its 
larve on wounds or moist surfaces. Cattle are most 
commonly attacked. 
In the British Isles Lucilia Cesar and Lucilia sericata 
are the commonest. 
Lucilia macellaria is common in America. 
Lucilia sericata is of a greenish-blue colour, and smaller 
than Lucilia Cesar, which has a golden sheen. 
The former has the first ring of the abdomen black, 
and the latter the first two rings. These flies deposit 
their eggs on the fleece of sheep, particularly round the 
anus or where there is a wounded surface. 
The eggs hatch the same day. 
Cupri sulph. is the best agent in use for the purpose 
of destroying the larve. 
