44 ENTOZOA FOUND IN MAN. 



Geyms Spiroptera. 



The spiropterse, which derive their name from the 

 spiral tail of the male furnished with membranous, 

 or vesicular, expansions, are found in vertebrated 

 animals, and principally in the mammiferae and in 

 birds. 



They often Hve between the coats of the stomach, 

 or else in tumours situated in this organ, or in the 

 oesophagus ; they are rarely found in other regions ; 

 a very small number exist in a free state in the cavity 

 of the intestine. 



The only species which has been observed in the 

 human subject is the Spiroptera hominis, which is 

 stated by Mr, Lawrence to have been present in the 

 urine of a female who passed a consideiuble number 

 of these entozoa.^ This species is doubtful. 



Genus Trichina. (Owen). 



This is a genus formed by Professor Owen, in 

 order to include a small nematoid worm, the Trichiua 

 Spiralis, which is found, enclosed within a cyst, in the 

 striated muscles. 



It is a very minute cylmdrical worm, coiled up 

 into two, or two and a half spiral turns ; when it is 

 unrolled, it measures about -^th of an inch in length, 

 and 7-^0 th of an inch in diameter. The long axis of 

 the cyst, within which the trichina is contained, lays 

 between, and parallel to, the fibres of the muscle.^ 



^ This case is recorded in the " Medico- Chirurgical Transac- 

 tions," for 1812. 



''' For a representation of this eutozoon, see Fig. 14. 



