8 



opinion. The parasite is well known in France and Germany, and has been 

 detected in pigs from the United States ; but even if it exists largely among 

 pigs in this country it is not likely that it would be looked for. 



A nematode of considerable size, Ascaris suilla, is sometimes found in the 

 small intestines of the pig. The worm very closely resembles the Ascaris 

 lumbicoides of man, but is more slender. 



Two rare nematodes of small size, ^sophagostoma dentatum and Globo- 

 cephalus mucronatus are referred to by some writers, but they are not recognised 

 in this country. 



TKICOCEPHALUS CRENATUS is not uncommon in the cseclum and large 

 intestines of the pig, and is only distinguished from the variety which is com- 

 mon to the sheep by the presence of small spines on the spicule. The eggs 

 contain embryos in a well developed form ; and, according to Leuckart, if they 

 be introduced into the digestive canal of the pig, they are rapidly developed, 

 and aquire the adult character in about four weeks. 



TRICHINA SPIRALIS is a form of nematode which infests the muscles of the 

 pig, and possesses special interest on account of the effects of the consumption 

 of the infected pork by the human subject. In the muscles of some the larval 

 trichinae may remain coiled up in their capsules for any length of time without 

 causing any disturbance which indicates their presence when portions of flesh 

 containing encapsuled trichinae are given in an uncooked or underdone state to 

 human beings or any susceptible animals. The larval worms escape from 

 their capsules in the digestive canal, and soon become mature and deposit eggs 

 which are quickly hatched, setting free young worms, which proceed at once 

 to bore their way to the muscles, in which they coil themselves and become 

 invested with a distinct membrane forming the capsule in which the worm 

 rests, unless it is swallowed by a warm-blooded animal. In man the process 

 of migration of all young worms into the muscles is attended with very severe 

 pain and fever. The general symptoms are not unlike those of acute rheu- 

 matism, with which trichiniasis is said to be often confounded. A certain 

 percentage of persons who suffer from eating underdone trichinised pork die from 

 .the acute pain and fever ; and others recover after much suffering, and do not 

 experience any inconvenience from the presence of encapsuled worms in the 

 muscles. It is obvious that no treatment can be applied directly to parasites ; 

 but the prevention of the disease is assured by the thorough cooking of pork 

 and the rejection of the meat as an article of diet when it is seen to be infested 

 with trichina. 



Trichiniasis is known among swine in Germany and in America ; but there 

 are exceptionally few instances of the discovery of the parasite in English pigs. 



