PARASITES. 91 



wliicli lodged twenty-four Filarise lohatos in its lungs, 

 sixteen Syngami trachealcs in the tracheal artery, besides 

 more than a hundred Spiropteras alatse within the mem- 

 branes of the stomach, several hundreds of the Holosto- 

 mum excavatum in the smaller intestine, a hundred of 

 the Dlstoma ferox in the large intestine, twenty-two of 

 the Dlstoma hians in the cesophagus, and a Dlstoma 

 echinatum in the small intestine. In spite of this affluence 

 of lodgers the bird did not appear to be in the least 

 inconvenienced. 



Krause, of Belgrade, mentions a horse two years 

 old, which contained more than five hundred Ascarides 

 megalocephalve, one hundred and ninety Oxyures curvujse, 

 two hundred and fourteen Strongyli armatl^ several mil- 

 lions of Strongyli tetracanthl, sixty-nine TsenicG per- 

 foliatse, two hundred and eighty-seven Filarise papillosae, 

 and six Cysticerci. When we consider how many eggs a 

 single worm produces, we can understand how it is that 

 so few animals escape being invaded by them. * 



Sixty millions of eggs have been counted in a single 

 nematode, and in a single tape -worm, or rather in a 

 colony, even a thousand millions of eggs. Even the 

 very animals which live as parasites, harbour others in 

 their turn. We find parasites on parasites, as we find 

 messmates upon messmates. Almost all writers on this 

 subject give examples of these; some in the larvae of 

 ichneumons, others in the lern£eans, and we have more 

 than once met with nematodes in different Crustacea still 

 attached to their host. 



In order to understand thoroughly the living furni- 

 ture of an animal, especially of a fish, it is necessary to 

 examine it while young ; the feces are the Kitchen-mid' 



