414 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1939 



The EntozooD he supposes to be the Ti-ichina spiralis, heretofore considered 

 as peculiar to the human species. He could perceive no distinction between it 

 an(d the specimens of T. spiralis which he had met with in several human 

 subjects in the dissecting-rooms, where it has also been observed by others, 

 since the attention of the scientific public has been directed to it by Mr, Hilton 

 and Professor Owen. 



In March 1866, 20 years after Leidy communicated his finding of 

 trichinae in pork, that investigator (2) explained at a meeting of 

 the same academy the circumstances under which he had made this 

 important discovery. Briefly the circumstances were as follows: 

 While eating a slice of pork, Leidy observed some minute specks in 

 the meat which reminded him of similar spots that he had seen in 

 the muscles of a human cadaver only a few days previously. He 

 saved part of the pork, and upon examining it microscopically he 

 found it to be copiously infested with trichinae. The parasites were 

 all dead, since the piece of pork in question had been thoroughly 

 cooked. It is noteworthy that Leidy was quoted as observing that 

 all meats were liable to be infested with parasites. He stated, how- 

 ever, that there was no danger in this to human beings, provided the 

 meats were thoroughly cooked. Leidy stated that he had satisfied 

 himself by experiment that parasites were destroyed when subjected 

 to the temperature of boiling water. 



As far as is known, Hilton (3), a prosector in Guy's Hospital, Lon- 

 don, was the first to investigate the white, gritty specks found by 

 him in a human cadaver; there is some evidence that similar specks 

 were found by Tiedemann, in 1822, and by Peacock, in 1828. In 

 1832,^ Hilton examined these pathological spots without recognizing, 

 however, any parasites within them. In 1835, Paget, then a medical 

 student in London, found whitish spots in a human cadaver which 

 he dissected in St. Bartholomew's Hospital. With the aid of Brown 

 and Bennett, Paget demonstrated that the white, gritty spots were 

 capsules which contained spiral worms. These worms were described 

 in the same year by Kichard Owen (4), and named by him Trichina 

 spiralis. In 1895, Railiiet (5) renamed these parasites Trichinslla 

 spiralis because the generic name Trichina^ proposed by Owen, was 

 preoccupied and, under the rules of zoological nomenclature, was not 

 available for the parasite under discussion. 



From the time of the discovery of trichinae in human cadavers 

 until 1860, these worms were regarded as zoological curiosities, 

 although, according to Leuckart (6), Wood, in Bristol, discovered 

 numerous trichinae in the body of a young man who died in 1835, 

 after a 3-weeks illness characterized by rheumatic symptoms, accom- 

 panied by cardiac and pulmonary inflammation. According to 



" Ills observations were published in 1833. 



