PARASITES. 97 



Among other instances, this naturalist mentions the 

 case of a boy of twelve years of age, -who, in 1699, after 

 suffering acute pain, voided from the intestines nearly 

 one hundred and sixty four millipedes, four scolopendrse, 

 two living butterflies, two worm-like ants, thirty-two 

 brown caterpillars of different sizes, and a coleopterous 

 insect. These animals lived from three to twelve days. 

 This is not all : the same child, two months afterwards, 

 voided four frogs, then several toads, and twenty-one 

 lizards, and sometimes a live serpent was seen for a 

 moment at the bottom of his mouth. Happily for 

 science, we do not see such things seriously related in 

 books at the present day. 



The size of parasites is very various : Boerhaave 

 mentions a bothriocephalus three hundred ells in 

 length ; at the Academy of Copenhagen, it was reported 

 that a solitary tape-worm {Taenia solium) had been 

 found eight hundred ells long. Female strongyli have 

 been seen from two decimetres to one metre in length; 

 and Gordii of two hundred and seventy millimetres. 

 We have found in a fish a worm which lived rolled up 

 like a ball, and which measured, when unrolled, more 

 than a metre. 



Parasites present an extraordinary variety of forms, 

 and the differences between the sexes in size as well 

 as in appearance are greater than in any other group 

 of animals. The male of the Uropitrus paradoxus, the 

 Urubu of Brazil, has the usual form of a round long 

 worm, while the female resembles a ball of cotton, without 

 the slightest analogy with the other worms of the order. 

 The Lernaeans also have females excessively various in 

 size and appearance, while the males generally resemble 



