3 82 



THE ANIMAL PARASITES OF MAN 



o*oi6 mm. broad, again reach the lumen of the intestine, 1 and grow to 

 double or three times that size, until they are passed out with the 

 faeces. They already differ from the parent (?) in the shape (rhab- 

 ditiform) of the oesophagus. When the external temperature is 



sufficiently high (26 to 



..-'$ 35 C.), they become 



// sexually mature after 



Nerve-ring ^ffiff moulting. Ill about 



;/!\:jt Excretoiy pore thirty hours they are com- 



pletely developed and 

 copulate, now forming 

 the free-living rhabditi- 

 form generation. At 

 Ovary, anterior lower temperatures the 



Anterior oviduct larve nl y m ult > but 



do not escape from the 



Anterior receptaculum . . 



seminis old cuticle and do not 



Ovary, anterior 



Ovary, anterior 



Posterior seminal receptacle 



Vulva 



Ovary, posterior 



" 



Genital 

 rudiment 



/ O\aiy posterior 



FlG. 273. Strongyloide^ 



r ... stercoralis : larva from fresh 



FlG. 272,-Strongylotdes stercorats female ; free-living human feces> x (After 



generation. x 170. (After Looss.) 



Looss.) 



develop further. At a temperature of about 25 C. only some of the 

 larvae attain maturity. 



1 As a case published by Teissier shows, they may also abnormally appear in the blood 

 (Arch. mtd. exp&r. et d'An. path., 1895, vii, p. 675). 



