524 THE ANIMAL PARASITES OF MAN 



Genus. Linguatula, Frohlich. 

 Linguatula rhinaria, Pilger, 1802. 



Syn. : Tcenia rhinaria, Pilger, 1802 ; Polystoma tcenioides, Rud., 1810; 

 Linguatula tcenioides, Lam., 1816 ; Pentastoma tcenioides, Rud., 1819. 



The male is white in colour, 18 to 20 mm. in length, anterior 

 portion 3 to 4 mm. in breadth, posterior part 0*5 mm. in breadth. 

 The female is of a yellowish colour, 8, 10, or 13 cm. long, 

 anterior part 8 to 10 mm. and posterior part 2 mm. wide. The 

 brownish eggs can be seen in the median line. The body is 

 elongated, rather flat, and exhibits about ninety rings 

 or segments with crenellated borders. The hooks 

 round the mouth are strongly curved and are articu- 

 lated to a basilar support. Eggs oval, 0*09 //, in length, 

 o'oy /A in breadth. 



L. rhinaria, in the adult con- 

 dition, lives in the nasal cavity 

 and frontal sinus of the dog, 

 wolf, fox, horse, goat, and 

 occasionally of man ; it causes 

 severe catarrh, epistaxis and 

 suppuration. 



Development. The ova, 

 which are found in masses in 

 the nasal mucus, already possess 

 an embryo ; they are expelled 

 with the nasal secretion, and 

 are swallowed by herbivorous 

 mammals with their food, 

 mostly by hares and rabbits, 

 but also by sheep, goats, oxen, 

 horses, antelopes, fallow deer, 

 pigs, cats, and occasionally also 

 by human beings. The young 

 larvce hatch out in the stomach ; 

 they possess a thickened an- 

 terior body with rudimentary 

 mouth parts and two pairs of 

 limbs ; the body gradually tapers to a short tail. 



The larvae of the Linguatulidce bore through the intestinal wall 

 and reach the liver, more rarely the mesenteric glands, etc. ; they 

 nere become encysted and enter a sort of pupal stage in which they 

 lose their limbs ; after several moultings and gradual growth the 

 second larval stage, having the appearance of the adult Linguatula, 



FIG. 371. Lingua- 

 tula rhinaria : fe- 

 male. Natural size. 



FIG. 372. Larva of 

 Linguatula rhinaria 

 (Pentastoma denticula- 

 tum). Enlarged. (After 

 Leuckart.) 



