Larger Parasites. 



147 



If the bones are not softened tlie point to be perforated 

 must be ascertained from the symptoms. If tlie sheep 

 turns to one side, open a little in front of the correspond- 

 ing ear and about half an inch from the median Mne oi 

 the skuU. If the head is elevated and the walk straight 

 forward without much terror or disorderly movement, open 

 at the same level but in the median line. If there is awk- 

 ward, hesitating movement, much terror, flurry and 

 stumbling, open in the median line further back. A flap 

 of skin is to be dissected up from the bone, large enough 

 to admit a trephine one-eighth inch in diameter (in an 

 emergency a gimlet wiU do) with which the bone is to be 

 perforated. After this the cannula and trochar is used as 

 above advised. 



If more than one cyst should be present the operation 

 may require repetition, and with care recoveries often en- 

 sue. A bag of ice on tlie head may remove symptoms 

 but does not kill the worm. 



ECHINOCOCCUS DISEASE. 



The Taenia Echinococous, a tapeworm of the dog, not ex- 

 Fig. 2. 



Fig. 2 — ^Taenia Echinococcus magnified (Cobbold' 



Fig. 3. 



Fig. 3 — Portion of cyst and heads of Echinococcus. 



oeeding one inch in length, lives in it? cystic form aa 



