Cb. XI.] PLAGUE OF TICKS. 209 



vantageous. My experience in tropical countries has led 

 me to the conclusion that in such parts at least there is 

 one serious drawback to the advantages of having the 

 skin covered with hair. It affords cover for parasitical 

 insects, which, if the skin were naked, might more easily 

 be got rid of. 



No one who has not lived and moved about amongst 

 the bush of the tropics can appreciate what a torment 

 the different parasitical species of acarus or ticks are. 

 On my first journey in northern Brazil, I had my legs 

 inflamed and ulcerated from the ankles to the knees, 

 from the irritation produced by a minute red tick that is 

 brushed off the low shrubs, and attaches itself to the 

 passer-by. This little insect is called the "Mocoim' : 

 by the Brazilians, and is a great torment. It is so 

 minute that except by careful searching it cannot be 

 perceived, and it causes an intolerable itching. If the 

 skin were thickly covered with hair, it would be next to 

 impossible to get rid of it. Through all tropical 

 America, during the dry season, a brown tick (Ixodes 

 bovis), varying in size from a pin's head to a pea, is 

 very abundant. In Nicaragua, in April, they are very 

 small, and swarm upon the plains, so that the traveller 

 often gets covered with them. They get up on the tips 

 of the leaves and shoots of low shrubs, and stand with 

 their hind legs stretched out. Each foot has two hooks 

 or claws, and with these it lays hold of any animal 

 brushing past. All large land animals seem subject to 

 their attacks. I have seen them on snakes and iguanas, 

 on many of the large birds, especially on the curassows, 

 and they abound on all the larger mammals, together 

 with some of the small ones. Sick and weak animals are 



