HEWSON AND OTHERS ON THE VILLI. 43 



in the minds of the members of the Academy of Sciences of 

 Prussia, at a time when one of the first anatomists of Europe, 

 the celebrated Meckel, was of their number. 



According to this account the internal surface of the' small 

 intestines abounds with villi, and with the orifices of follicles. 

 These villi, are about the fifth part of a line in breadth. In each 

 of them is a cavity filled with a soft spongy substance, which 

 has one or more orifices communicating with the intestines, and 

 from which also proceeds a lacteal vessel. On the membrane 

 which forms this cavity, blood-vessels are most minutely rami- 

 fied. This cavity he calls an ampullula, and supposes it to 

 constitute the principal part of the villus. By injecting the 

 arteries of the intestine, he was able to pass a fluid through the 

 ampullula into the cavity of the gut ; he kept a stream of air in 

 this way passing through the ampullula until it was nearly dry 

 and stiff, and then laid it open with a fine instrument. From the 

 appearances which then presented, he inferred that the cavity of 

 the ampullula was occupied with a spongy or cellular substance. 

 Around each villus he found a number of mucous follicles, 

 which often were filled with a tenacious mucus : and distinct 

 from these must be the exhalent orifices, which discharged a 

 fluid injected by the arteries without passing through the 

 mucous follicles. 



Lieberkuhn died early, and left but one essay on this subject, 

 which was originally published in Holland, in 1744, but has 

 been republished by the Academy of Berlin, in their Memoirs ; 

 and also by Mr. John Sheldon, of London. 



This account of Lieberkuhn appears to have been admitted 

 by Haller : but it has been rigidly scrutinized by some of the 

 anatomists of London, who were particularly interested with 

 the subject, as they had paid great attention to the absorbent 

 system, and were very successful in the investigation of it. 



The late Mr. Hewson, whose opinion is entitled to the 

 greatest respect, rejected the idea of the ampullula, and believed 

 that the villi are composed of net-works of lacteals, as well as 

 arteries and veins ; although he added that " this is the only 



