238 THE ANIMAL PARASITES OF MAN 



allowed to be in the farmyards of the small farmers for the whole day or 

 allowed to wander in the village streets and pasture lands, they are more 

 liable to take up the oncospheres of the Tcenia solium than when shut up 

 in good pigstyes. 



The geographical distribution of Tcenia solium generally 

 corresponds with that of the domestic pig and the custom of 

 eating pork in any form insufficiently cooked or raw. There 

 are or were some isolated districts in Germany, France, Italy and 

 England where the " Armed tapeworm " was frequent (for instance, 

 Thuringia, Brunswick, Saxony, Hesse, Westphalia, whereas it is and 

 was very scarce in South Germany) ; it is thus easily understood 

 why it occurs very rarely in the East, in Asia and in Africa, in con- 

 sequence of the Mahommedans, Jews, &c., not eating pork. In 

 North America, also, Tcenia solium is very rare ; the tapeworm 

 which is known there by this name is generally Tcenia saginata 

 (Stiles). During the last decades tapeworm infection has, however, con- 

 siderably decreased in North and East Germany in consequence of the 

 precautions exercised by the public in the 'choice of pork to avoid 

 trichinosis, especially, however, because meat infected with cysti- 

 cercus must be sold for what it is and must be thoroughly cooked 

 before being placed on the market ; indeed, if badly infected it 

 may not be sold for food, but can be turned to account for industrial 

 purposes. 



The occurrence of Cysticercus cellulosce in man has been known 

 since 1558 (Rumler, Obs. med., liii., p. 32) ; there is hardly an 

 organ in man in which cysticerci have not been observed at 

 some time ; they are most frequently found in the brain, 1 where 

 they grow to a variety known as Cysticercus racemosus ; next 

 in frequency they are found in the eye, in the muscular system, 

 in the heart, in the subcutaneous connective tissue, the liver, 

 lungs, abdominal cavity, &c. The number of cysticerci observed 

 in one man varies between a few and several thousands. Of 

 the sexes, men are most subject (60 to 66 per cent, of the number 

 attacked). The disturbances caused in man by cysticerci vary 

 according to the nature or position of the organs attacked ; when 

 situated in the cerebral meninges they have the same effect as 

 tumours. 



1 Dressel, for instance, examined 87 persons suffering from Cysticercus, and 

 found it seventy-two times in the brain, thirteen times in the muscles ; K. 

 Miiller, in 36 cases, found it twenty-one times in the brain, twelve times in the 

 muscles, three times in the heart ; Haugg in 25 cases, found it thirteen times in 

 the brain, six times in the muscles, twice in the skin, &c. According to Graefe, 

 amongst 1,000 ophthalmic cases in Halle and Berlin, there was one with cysti- 

 cercus in the eye ; in Stuttgart there was only one in 4,000 ; in Paris one in 

 6,000, and in Copenhagen one in 8,000. 



