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oxen, horses, goats, antelopes and fallow deer, pigs and cats ;; 

 very rarely human beings. 



After being hatched in the stomach the larvae bore 

 through the intestinal wall to the liver, where they become 

 encysted. Several moultings take place, and the second larval 

 stage sets in; then they take on the adult form. Five to 

 six months after ingestion the Linguatula are 4-6 mm. long, 

 the mouth and intestine are formed, and the sexual organs 

 mature. 



This larval stage has been known for a very long time, 

 and as the parasite was regarded as a new one, the name 

 Pentastoma denticulatum was given. These larvae then be- 

 come very active and escape into the open by means either 

 of the intestine or bronchi, to complete their cycle by being 

 again sniffed up into the nose of a dog, wolf, or fox, occa- 

 sionally horse and goat, where, after being stationary for a 

 short time, another moulting takes place, and in six weeks' 

 time the parasites become adults. 



The Linguatula found in the dingo differs in many re- 

 spects from its relation in the dog. In tabular form this at 

 once becomes apparent : — 



Linguatula rhinaria. 

 (Dog.) 

 Male.— White. 



18-20 mm. long. 



Anterior portion, 3-4 mm. 



broad. 

 Posterior portion, 0*5 mm. 

 broad. 

 Female . — Yellowish. 

 8-13 cm. long 



Anterior portion, 8-10 mm. 



wide. 

 Posterior portion, 2 mm. 

 wide. 

 The brownish eggs are seen 

 in median line. 



Body. — Elongated, rather 

 flat, shows 90 rings or seg- 

 ments, with crenellated bor- 

 ders, anterior end rounded. 



Hooks. — Round, mouth 

 strongly curved, and are ar- 

 ticulated to a basilar support. 



Eggs. — Oval, *09 mm. 

 "07 broad. 



long 



Linguatula dingophila. 



Male. — Not discovered. 



Female. — Yellow, with brown 

 egg ridge. 



2 mm. high. 



3 cm. 1 mm. long. 

 Anterior portion, 12 mm. 



wide. 

 Posterior portion, 2 mm. 

 wide. 



The surface on which the 

 egg-ridge is placed is curved on 

 the flat, and so if a trans- 

 verse section were made, since 

 the other surface is quite flat 

 it would appear D-shaped. 



The anterior end comes to a 

 rough point; as the parasite is 

 so thick and very deep in 

 colour (preserved in Kaiserling) 

 it is impossible to determine 

 the mouth or hooks. 



Eggs. — More round than 

 oval, '05 mm. long x '025 wide.. 



