OXYURIDm 



Genus Lagochilascaris Leiper, 1909. 



Definition.^ — AscaridcB with dense cuticular lips and interlabia 

 surrounded by a ridge and furrow, separating the Hps from the rest 

 of the body. (Esophagus simple. Shallow ledge-like cuticular alse 

 extend along either side of the body to near the tail. Eggs mosaic. 



Type Species. — Lagochilascaris major Leiper, 1909, in the lion. 



Lagochilascaris minor Leiper, 191 o. 



This species has been found in the pus of subcutaneous abscess 

 in man in Trinidad. 



Morphology. — Males 9 millimetres in length by 0-5 millimetre 

 in breadth, with bent posterior part of body. Female 15 millimetres 

 in length, straight posteriorly. The vulva, with two projecting lips, 

 opens 6 millimetres from the anterior end. 



Hosts. — Possibty one of the Carnivora, Man is an accidental host. 



Habitat. — Probably intestinal in its normal host. The specimens 

 were found in abscesses under the skin in man. An allied species, 

 A. major, occurs in the intestine of the lion in East Africa. 



Family 10. Oxyurid^ Dujardin. 

 Genus Oxyuris Rudolphi, 1803. 

 T^Q^mXion—'Nematoda in which the three labial papillae are not 

 very distinct. (Esophagus long, with a double dilatation. Skin 

 markedly striated. Male with curved posterior end, one spicule, 

 and two pairs of pre-anal pa.pilk£. Female with straight posterior 

 end, which tapers to a point. Vulva in the anterior part of the body. 

 Type. — Oxyuris vermicularis Linnaeus, 1767. 



Oxyuris vermicularis Linnaeus, 1767. 



Synonyms.' — Ascaris vermicularis Linnaeus, 1767; Fusiaria ver- 

 micularis Zeder, 1803. 



Remarks. — Oxyuris vermicularis is the pin or thread worm, and 

 occurs, as far as is known, only in man and all over the world. It 

 is believed to live in the lower part of the small intestine at first, 

 and then the gravid females travel to the large bowel. It has been 

 known from the earliest times. 



Morphology. — It is a minute white round worm, with transversally 

 striated cuticle, which forms two ridges along the ventral and dorsal 

 surfaces corresponding to the lateral ridges. 



Male is 3 to 5 millimetres in length, with a spirally rolled posterior 

 extremity, with one spicule and six papillae. Female is 10 milli- 

 metres in length and 0-6 millimetre in breadth, with a long pointed 

 tail. 



Life-History. — The egg, when deposited from the uterus, measures 

 50 to 52 ^ by 16 to 24 iji, with a thin sheh and a fairly well-developed 

 embryo. The dorsal surface of the egg is more convex than the 

 ventral. These eggs escape in the faeces. They are then reintro- 



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