TRYPANOSOMA MELOPHAGIUM 



503 



the sheep trypanosome, as Woodcock had suggested. Noller pointed out 

 that its correct name was T. ^nelophagium. Kleine (1919a) also studied 

 the trypanosome, and came to the conclusion that the ked inoculated it 

 to sheep from its salivary glands. The whole question has been the subject 



Fig. 213. — Life-Cycle of Trypanosoma melopliagium in the Blood of the Sheep 

 AND IN the Ked [Melophagus ovinus) ( x 1,560). (After Hoare, 1923; from 

 Parasitology, vol. xv., p. 395.) 



1. Trypanosome in blood of sheep; form ingested by ked. 



2. Trypanomorphic crithidia form which leads to typical crithidia (4, 5) by division (3). 



3. Dividing form. 4-5. Typical crithidia forms in mid-gut. 

 G-8. Development of small crithidia forms in hind-gut. 



9 9«. Two methods of division of crithidia forms, giving rise either to small jiyriform crithidia 

 (10) or metacyclic trypanosomes (10a). By migration of the kinetojilast the crithidia 

 may become a metacyclic trypanosome (10, 10a). 

 106. Leishmania forms taking no part in cycle. 



of exhaustive investigation by Hoare (1922, 1923) in England. He has 

 shown conclusively that uninfected lambs can be infected by feeding them 

 with the hind-gut of infected keds, and, furthermore, that the bite of the 

 ked is unable to bring about infection. A study of the trypanosome in the 

 ked has shown that the flagellate produces metacyclic trypanosomes in 



