ACAEINA 445 



of the species use the insects only for transportation, being young ani- 

 mals in the nymphal stage which attach themselves by a pedicel of 

 excrement: as adults they live on the ground among fallen leaves, and 

 in similar places; several species. 



5. U. vegitans (DeGeer) (Fig. 699). Body 

 arched, smooth, brownish in color, about 1 mm. 

 long: common. 



FAMILY 8. AKGASIDAE. 



Ticks. No scutum, as in the Ixodidae; stigmal 

 plate between legs 3 and 4: 16 American species, 

 which are nocturnal parasites of domestic birds. 



ARGAS Latreille. With the characters of the family: about 10 

 species. 



A. persicus Fischer (A. miniatus Koch). The Miana bug. Body 

 oval in shape, 5 mm. long in the male and 10 mm. in the female and 

 brown in color: often a dangerous parasite of chickens from Florida to 

 California; cosmopolitan; in western Asia it bites persons and is much 

 feared. 



FAMILY 9. IXODIDAE.* 



Ticks. Body often large, and covered with a leathery integument 

 capable of great distention in the female, with prominent, slender legs 

 and beak-like mouth parts; anterior dorsal surface covered with a horny 

 shield, the scutum (Fig. 700, B), which in the male extends over the 

 entire back; articulating with the anterior margin of this is the head or 

 capitulum, on which in the female are 2 pitted spots; head bears the 

 short, thick, 3 or 4-jointed pedipalps at the sides and in the middle, 

 the elongated beak or rostrum, which is made up of the 2 mandibular 

 sheaths above, and the toothed hypostome or under lip beneath, with 

 the 2 mandibles between, the latter organs being toothed at the tip; 

 eyes present or not; tracheae present, the spiracles being just behind 

 the last pair of legs, each surrounded by a stigmal plate or peritreme 

 (Fig. 700, C) ; legs 6-jointed, ending with 2 claws and a pad, the foot 

 of first pair also bearing a sense organ called Haller's organ: parasitic 

 on mammals, birds, and reptiles; the female, when gorged with blood, 

 falls to the ground to lay her eggs; the young ticks, which have but 

 6 legs at first, usually ascend some plant and are brushed off by a 

 passing vertebrate which can set as a host; 250 species, about 35 

 American. 



* See "The Cattle Ticks of the United States," by D. C. Salmon and C. W. Stiles, 

 Rep. Bureau of An. Ind., U. S. Dept. of Ag., 1902, p. 380. "Ixodidae," by L. G. 

 Neuman, Das Tierreich, 1911. 



