LINGUATULA RHINARIA 389 



migrations are not essential for further development ; it is probable 

 that some of the larvae reach the nasal cavity direct by way of 

 the trachea, thus infecting herbivorous animals direct. In other 

 cases the infection of dogs, wolves, foxes, beasts of prey, takes 

 place through their devouring mammals or parts of them (liver, 

 lungs) which harbour the larval form ; it may be conjectured 

 that at all events most of the larvae are thus first imported into 

 the stomach of their hosts, and thence, having bored through 

 the intestinal wall and diaphragm, invade the lungs, and by way 

 of the bronchi, trachea, &c., finally find their way to the nasal 

 cavities ; possibly also some larvae find their way to the nasal 

 cavities from the mouth while the food is being masticated. 

 After becoming stationary another moulting takes place, the 

 cuticle with the pointed edges is discarded, and the parasites 

 become adult after six or seven weeks. 



Linguatula rhinaria has been observed in man in the adult as 

 well as in the larval condition (Pentastoma denticulatum}. Zenker first 

 called attention to the occurrence of the larva in man, having found it 

 nine times in the liver in 168 autopsies. Heschl found it twice in Vienna 

 in 20 autopsies, Virchow found it in Wiirzburg and Berlin, Wagner in 

 Leipzig (10 percent.), and Frerichs in Breslau five times in 47 autopsies. 

 The parasite is much less frequent in Switzerland. According to Klebs, 

 one case occurs in 900 autopsies, and according to Zaeslin two cases 

 occurred in Basle to 1,914 autopsies. In the seamen's hospital in Kron- 

 stadt Pentastoma denticulatum has been found six times in 659 autopsies. 

 It was almost always the liver that contained one or a few specimens. 

 The parasite was very rarely found in the kidney or spleen, or encysted 

 in the intestinal wall. The adult Linguatula rhinaria is far more rarely 

 observed in man. 



A case reported by Landon that related to a blacksmith of Elbing is 

 particularly interesting. This man accompanied the campaign of 1870 ; 

 he soon, however, fell ill with pains in the liver, accompanied by icterus 

 and intestinal disorders. Soon after the war, and after the symptoms 

 were reduced to icterus and weakness, bleeding of the nose set in and 

 continued with slight intermissions for seven years ; an unpleasant sensation 

 of pressure in the left nasal cavity set in with inflammatory swelling of 

 the mucous membrane. At last, in the summer of 1878, when the pres- 

 sure in the nose had considerably increased, a Linguatula was expelled 

 from the nose with a violent attack of sneezing, and lived for three days 

 longer in water. The bleeding of the nose then ceased, and the patient 

 soon recovered. There can be no doubt that the first illness was con- 

 nected with the invasion in the liver of numerous larvae of Pentastoma-, 

 and disappeared after their encystment ; one or a few of these must 

 subsequently have found their way to the nose and settled there. 1 



1 Schubart, T. D., " Entw. v. Pent, tanioides " (Z. /. w. Z., 1852, iv., p. 116). 

 Zenker, F. A., " Ueber einen neuen thier. Paras, d. Mensch." (Zeitschr. /. rat. Med. 



