ASCAlllD.K AND FILAEIDiE. 



87 



expels many females full of eggs, and immature forms. A long- 

 tailed dimorphic form called Mastigodes (fig. 36) has been 

 described by Nitzsch. Males are comparatiuoly rare. These 

 worms, I have observed, are passed usually in the morning, 

 generally numbers together, the excreta of the host being full 

 of their ova. Very closely related is the obnoxious little human 

 worm, 0. vermicularis. 



The Filaridse are filiform worms, all of which are found in 

 connective tissue or blood 

 and never in the intestine. 

 A common form in the 

 horse is Filaria papillosa, 

 a white worm about six 

 inches long found in the 

 peritoneal cavity. Thou- 

 sands have been taken out 

 of the thoracic cavity of 

 the horse at one time. 

 They sometimes even pene- 

 trate the scrotum. The 

 life-history of this worm, 

 like many others, is quite 

 unknown. Another species, 

 known as F. immitis, is 

 found in the heart and 

 pulmonary artery of the 



dog. Neither, however, occasions sufficient loss to call 

 further remarks. 



Filaria also are parasitic in man, causing Elephantiasis or 

 Filariasis. These small blood and lymph parasites are carried 

 by mosquitoes (Culicidse), as is also the F. immitis of the dog. 



Thymol administered as stated in Appendix I. is certain to 

 free the intestines of Ascarid parasites. For Filaridce it is a 

 matter of prevention. 



Fig. 35. — Oxyubes of Horse. 



Females with .short tails (=Cmula). Rail- 

 lie t. (From Neumann. ) 



for 



