32 



belonged, and specific differences were found in slight but con- 

 stant peculiarities in relative length and breadth, and in the 

 confoi'mation of excrescences on the surface of the shell. 



Dr. R. T. Leiper also gave a demonstration on the " new " 

 rabbit disease. Examina.tion of a large number of rabbits shows 

 that the chief cause of mortality is a coccidial invasion of the 

 intestinal wall or of the lining of the bile-ducts. According to 

 Fantham and others the causal agent in both types of disease is 

 Ewieria stiedce, but Dobell holds that the intestinal lesion is due 

 to a distinct species. In many cases changes in the liver attri- 

 buted to coccidiosis were the res\ilt of infection with Cysiicercus 

 pisiformis, the larval stage of the dog tapeworm Tcenia serrata. 

 Large swellings in the region of the head and neck, suspected to 

 be cancerous, were due to Coenusus serialis, the larva of the 

 dog tapeworm Tcerda ccenurus. Of relatively small economic 

 importance are infections with the threadworm Oosyuris amhiguus 

 and the tapeworm Ctenotcenia leucharti. There is some evidence 

 that a bacterial infection may occasionally be the cause of death. 



The coccidial infections pass from infected to healthy animals 

 through the fseees. When freshly passed the coccidial oocysts 

 are not infective. They only become so after a period of delay 

 in which certain developmental changes take place. These 

 changes proceed more rapidly in dry than in wet faeces. Pre- 

 vention depends upon the systematic periodical removal and 

 destruction by burning of all pellets and contaminated bedding, 

 and the use of some fluid which will destroy such oocysts as 

 remain in the hutch. 



Although several cases of coccidial infection in man have been 

 recorded, Dobell maintains that in none of these cases is Eimeria 

 stiedce the causal agent. There would appear therefore to be no 

 risk of infection to man. 



The cystic stages of the tapeworms of the dog appear to occur 

 chiefly in those rabbits fed with dandelions and other green 

 stuffs collected from the roadsides, whei-e the vegetation is 

 especially liable to contamination with f feces of dogs which have 

 acquired their infections from eating uncooked rabbit ofial. 



