39 



mature condition in almost all animals, but mostly in the 

 Carnivora. Man harbours no less than ten species. 



If the mature joints or proglottides are administered to 

 an animal, in twenty-four hours minute embryos are found in 

 the blood, and are carried along to the liver, where they form 

 a colony of cysts. After a time they escape by pushing their 

 way through, take up their abode in other parts of the body, 

 and undergo a second encystation, which takes place in about 

 eight weeks. If these cysts are administered to some other 

 animal, the larva is set free in two or three hours, and in three 

 days shows indications of becoming jointed ; in twelve days 

 they are four inches long, and become sexually mature in 

 about a month. The Proglottides are furnished with male and 

 female organs of generation, but are not capable of self-im- 

 pregnation, as was formerly supposed, 



Mr. West then minutely described the anatomy and life- 

 history of the most common one infesting man, the Tcenia 

 solium, and stated that they had been found 10 ft. 2 in. in 

 length, and containing 825 segments. He also described the 

 Tcenia echinococcus, which causes one-seventh of the annual 

 mortality of Iceland. 



The TetrarhynchidcB infest the marine vertebrata. Having 

 described the life-history of this worm, Mr. West concluded 

 by a few words of advice how to avoid becoming infested with 

 Entozoa. The remedy is very simple ; partake of no animal 

 food but what is thoroughly cooked, nor any vegetables that 

 have not been thoroughly washed or boiled. Butchers through 

 their ignorance frequently infect themselves ; they place the 

 knife between their teeth that has been used to cut up a 

 diseased animal, the ova thus get transferred to their stomachs. 



The paper was well illustrated by diagrams and specimens 

 of the various Entozoa under microscopes. 



APRIL xyh, 1886. 

 R. ADKIN, Esq., F.E.S., President, in the Chair. 

 Mr. A. W. Mera exhibited Syntomis phegea, L., bred 

 from ova deposited by a female captured in Italy. 



