THE ACAKINA OR MITES. 



69 



Fig. ISO.— Ixodes marxi: Female. 

 (Original.) 



several small yellow marks on the brown scutum. Several species are yellowish, 

 with irregular brownish marks. A. cajennense Fabr. (fig. 123) is one of them and is 

 abundant in the tropics of America, extending up into Texas. A. maculatum Koch 

 is a handsome species with rich brown and yellow markings, not unlike a Dermacentor. 

 It has but one spine on the front coxae, while other species have two spines. One very 

 large species, A. tuberculatum Marx, occtirs in Flor- 

 ida on the gopher or tortoise. Some hairy species 

 occur on the giant tortoises of the Galapagos Islands. 

 A. dissimile Koch is quite common in the American 

 tropics and is sometimes taken on bullfrogs. None 

 of the species occur in the Western United States, 

 an interesting fact of distribution. None of our spe- 

 cies of Ainhlyoinma have as yet been associated with 

 the dissemination of any disease, but all are likely 

 to attack man and the domestic animals. In South 

 Africa A. hebraeum Koch, commonly known as the 

 "Bont tick," transmits heart water to sheep and 

 calves, but occurs on a great variety of animals, 

 both wild and domestic. 



The genus Haemaphysalis (formerly called Rhipi- 

 stoma) is represented in our country by but three spe- 

 cies; one, H. leporis-palustrid Pack., is very common 

 on rabbits, especially in the South and West. The 

 young are often found on the heads of birds that 

 nest on the ground, but the adults of this species are 

 rarely taken on bu-ds. H. chordeilis Pack. (fig. 126) 

 is usually found on birds. It has been taken in Vermont on turkeys and is 

 said to be a serious pest, the ticks sometimes being so abundant on young turkeys 

 as to kill them. H. expositidus Koch, a European species, has been recorded from 

 Manitoba on cattle. Verj^ possibly it was imported, but it appears to be well estab- 

 lished. This species in Europe is often troublesome on 

 sheep. The genus is much better represented in Africa, 

 India, and Insulinde, but in all cases the species are 

 rather smaller than other ticks. 



Of the genus Ixodes (figs. 127, 128, 131) we have a num- 

 ber of species, several of which are known from but few 

 specimens. Ixodes coohei Packard is the common form in 

 the East, where it occurs on a great variety of small 

 animals. /. marxi Banks (fig. 130) occurs on squirrels. 

 In the West, I. angustus Neumann is common on the 

 Pacific coast, while I. kingi Bishopp occurs on many small 

 mammals in the Rocky Mountain region. In the South, 

 /. scapularis Say (fig. 129), a reddish species with almost 

 black legs, is very common, especially in Florida. Most 

 of the species are partial to small mammals and the males 

 are much less common than the females. In Scotland 

 I. ricinus Linn, often attacks sheep and appears to dis- 

 tribute the germs of a disease similar to Texas fever that 

 is known by the name of "louping-ill" or "trembling." 

 The parasite is at present unknown. The loss to Scottish herders is sometimes very 

 hea\'y. It is said that sheep in moist meadows are not as subject to ticks as those in 

 drier pastures. Numerous species of Ixodes are found tliroughout the world and are 

 perhaps more abundant in mountainous parts of temperate countries than elsewhere. 

 The few species of Ceratixodes (fig. 132) occur on large sea birds which live in cold 

 regions. The same species has been taken in the Arctic and Antarctic regions. 



Fig. 131.— Ixodes: Venter of 

 male. (Original.) 



