SHEEP-NOSTRIL MAGGOT. 
128 
thorougly suited both for progression up the nostrils and hanging on to 
the coating, and also for keeping their breatliing-pores safe from being 
choked by moisture, but by no means suited for living in the brain. 
Upper surface of the brain showing an hydatid.* 
The form and very special apparatus of the head and tail are 
adapted for movement and for holding on, —not for lying in a sur¬ 
rounding soft substance. Likewise the maggot possesses a breathing 
apparatus of spiracles so placed at the end of the tail that under 
special circumstances, and at the will of the maggot, these spiracles may 
be protected by the upper rim of the end segment in which they are 
placed being drawn down over them, so as to meet the projecting lobe 
below, and thus by closing over them (much like the lips over the 
teeth) preserve these breathing-pores from being choked up by any 
special flow of fluid matter down the nose. This apparatus has an 
obvious use in the nostrils, but in the brain the maggot would be 
so closed in by surrounding matter that the air would have no 
access 'to the breathing apparatus whether open or shut. As these 
maggots live in maggot state for about a year,—and (supposing them 
to live in the brain at all) almost the whole of their year’s life would have 
to be passed in it, because they could only pass in whilst still in most 
* For the history of the Ccenurus cerebralis or Hydatid, which in its young 
state causes “gid” in sheep, and subsequently develops to tapeworm in the 
bowels of the dog, in cases where the dog has fed on the uncooked infested brain, 
the reader is referred to information given in Chapters vii. and x. of ‘ The Internal 
Parasites of our Domesticated Animals,’ by Dr. Cobbold, where some very plain 
and serviceable remarks are added as to the part played by dogs in distributing the 
eggs of the tapeworm so as to start new attack in the flock. I have also especially 
to acknowledge the kind assistance given me by Mr. H. Bullock, F.R.C.S., of Spring 
Grove near Isleworth, in helping me to make a careful examination of the first 
hydatid infested head, which otherwise I could not have fully studied, 
