BY N. A. COBB. 185 



Confectionery.* 



Vegetables and fruit eaten raw. 



Bread, cakes and pastry. 



Cigars and cigarettes. 

 From table utensils (najjkins, toothpicks, &c.). 

 From drinks. 

 From breathing dusty air (clouds of dust on the streets, 



dusty air when clothing or carpets are dusted). 



EXPLANATION OF PLATE. 



a. — Anus. 



h. — Posterior bulb of the cesophagus. 



c. — Constriction in intestine. 



d, — Two large cells at the head. 



e. — Ampulla. 



/. — Margin of the lateral field. 



i. — Intestine. 



j. — Jugular cells. 



I. — Muscle cells. 



m. — Median bulb. 



n. — Nerve-ring. , 



0. — Mouth. 



p. —Porous area on the egg. 



s. — Sexual organs. 



t. — Cuticula. 



V. — Ventral gland, 

 Fig. 1. — Anterior extremity of the egg of Oxyuris vermicular is 

 in optical section, showing the position of the porous area. 

 X 1300. 

 Fig. 2. — Larva of Oxyiiris vermicularis, not yet six hours old, 

 hatched under normal conditions in the human stomach, x 900. 

 Figs. 3, 4, and 5.— Different stages in the development of the excretory 

 organ of Oxyuris obvelata. Highly magnified. Fig. 5 

 shows the gland bifurcated. 



* There is a common belief that confectionery eaten freely is productive of 

 thread-worms. Confectionery being often more or less sticky is very well 

 adapted to carry the eggs, but the worms which become troublesome soon 

 after its consumption are not a direct but an indirect result. Eaten in 

 undue quantity sweets cause acidity from which the worms flee, soon 

 making their appearance near the anus and becoming troublesome. They 

 are worms that were already piesent, — were not imported with the sweets. 





