108 



The fact of slow development and continuous infection are the main 

 points brought out in this experiment. Continuous infection is natu- 

 rally one of the results where tcenice are constantly developing and 

 shedding ripe proglottides laden with embryosfor the infection of other 

 hosts. Continuous infection also leads me to suspect that no interme- 

 diary host is necessary for the contir.uance of the life of the embryo. 

 This proceeds from the fact that no single species of mollusk, insect, or 

 other animal is to be found at all seasons and places necessary to suit 

 all the conditions under which we find the host infected. 



JSxperiinent No. 2. — A lamb dropped at a slangliter-lioiise in this city was kept with 

 its mother in an uninfected stall. 



The Unib was fed on Jannary 10, 1887, with a large quantity of proglottides of 

 Icenia expansa from No. 108. The embryos were found to be alive and moving before 

 feeding. 



On March 20 the same lamb was fed with proglottides of T. fimbr'mta from No. 103. 

 These contained live embryos on the 18tli instant. 



On March 29 fed the same lamb with proglottides containing embryos of T.^minato 

 from No. 101. 



On April 19 this lamb was killed and nothing was found except a few white spots 

 in and on the liver. The experiment bad no results. 



AN EXPERIMENT I'D INFECT LAMBS WITH TiENIA FIMBKIATA. 



JEx2)erimen.t No. 3. — May 23, 1837, placed fifteen ewes with unborn lambs in three 

 box-stalls. They were fed on alfalfa, hay, corn, and bran. Their water was drawn 

 from a hydrant nearby. The ewes being thin in flesh, and taken from the prairie 

 grass and placed upon dry feed, thrived but poorly. Between May 23 and May 29 

 eleven lambs were born, which lived until the close of the experiment. Five of the 

 largest and oldest were placed with their mothers in stall No. 1. The remaining were 

 divided between two stalls, Nos. 2 and 3. 



These animals were removed from all sources of infection through 

 food and water, and the lambs had never been exposed to any source 

 of infection. The ewes were suspected of being infected with T.fim- 

 hriata. If the lambs became infected they would either take them of 

 their mothers or from their feed. Between May 26 and June 15 the 

 lambs were fed in stall A several times each with a number of ripe 

 proglottides from adult tmnicv. An interval was left between each 

 feeding, and each lamb was fed at least three times. The other lambs 

 were not fed. All but two of the ewes were found to contain adult 

 tcenice when examined later. 



The lambs and ewes were killed in nearly equal lots on June 25, July 

 15, and August 1. 



.Tune 25, killed one ewe and one lamb from pen No. 1, two ewes and one lamb from 

 No. 2, and three dry ewes from No. 3. Lambs uninfected. One ewe had tainia2''"' 

 long. 



July 15, killed two ewes and two lambs from No. 1, two ewes and two lambs from 

 No. 2. Lambs uninfected. 



August 1, killed two ewes and two lambs from No. 1, and two ewes and two lambs 

 from No. 2. Lambs uninfected. 



