CESTODE INFECTION IN CHICKENS 



233 



proglottids. Ill several instances when the flies were hungry it 

 was observed that they would take small fragments of the proglot- 

 tids between the labella of the labium and actually devour them. 

 Since the eggs are microscopic in size it is practically certain that 

 the flies got some of them. 



Several Calliphora were fed on eggs from this species, but 

 these flies lived for only two or three days. 



Proglottids of this tapeworm were fed to a number of beetles 

 of the species Tenehrio melitor. The beetles ate the segments 

 readily. Some were killed at the end of one week, others at two 

 weeks, and the rest at three weeks. These beetles were sectioned, 

 but showed no developmental stage of cestodes. 



Davainea tetragona. In experiments on this species 59 flies 

 in all were used. Some of these were killed and preserved after 

 from two to twelve days. The proglottids were broken up and 

 the eggs set free in a drop of water. The flies lapped up the water 

 with the eggs and afterwards sucked all of the moisture from the 

 ^fragments of the proglottids. Therefore, it is very probable that 

 the flies got some of the eggs. Microscopic examinations of the 

 droppings of the flies showed no signs of eggs. 



Material would pass through the flies in a few hours as was 

 demonstrated by feeding them on blood. When the flies gorged 

 themselves with blood they passed red droppings in from eight to 

 ten or twelve hours. This indicated the length of time that it took 

 material to pass through the alimentary canal. In this way the 

 approximate time to make fecal examinations for the eggs was de- 

 termined. However, examinations were made of the droppings 

 after five or six hours as well as later and at regular intervals of 

 two or three hours. 



The flies were fed on eggs once or twice each day for three days. 

 When they were fed once a day that was done in the morning, and 

 when fed twice they were given one dose in the morning and the 

 other at noon. On three occasions some flies were fed in the even- 

 ing and fecal examinations were made the next morning and con- 

 tinued at intervals of two or three hours. 



The flies were all sectioned and examined, but showed no stages 

 of the cestodes in any instance. 



Some Calliphora were fed upon the eggs of this species, but 

 they did not live more than two or three days. Some beetles, Ten- 

 ehrio, were fed on proglottids, but upon examination they showed 

 nothing. 



