NON-PSOROPTIC FORMS OF ACARIASIS. 645 



NON=PSOROPTIC FORMS OF ACARIASIS. 



These are produced in farm animals by arachnide belonging to the 

 families of Trombidiids and Ixodidas. 



(1.) The Leptus autumnalis is considered to be the larva of the 

 TrombiJium Holoscrici uiii, or silky trombidion. It lives in late sunnner 

 and autumn, in the grass. 



Symptoms. The animals show intense itching, and cannot sleep 

 owing to burning sensations. They continually rub themselves, and 

 thus, secondarily, produce excoriated papules and patches resembling 

 those of eczema. When the papules are very numerous, particularly 

 if the animals are thin-skinned, more or less extensive erythema may 

 be produced. 



At the points attacked the skin swells, becomes red, and sometimes 

 even violet, and exhibits irregular, isolated or confluent swelhngs, j- 

 to f of an inch in diameter. 



The parasite most commonly becomes fixed round the lips, the fore- 

 head, the cheeks, the sides of the neck, and the extremities. 



The diagnosis is easy, the discovery of the parasite removing all 

 doubt. 



The condition is of slight importance. The parasites do not live for 

 more than a few days on the animal's skin, so that they only produce 

 temporary disturbance. 



Treatment consists in bathing the parts with some lotion, such as 2 

 to 3 per cent, creolin or 2 per cent, chloral, or in applying mixtures 

 of oil and petroleum, etc. 



(2.) Ixodes hexagonus, I. ricinus, and other species of the tick family 

 (Ixodidfe) attack sheep, goats, and oxen in France. 



Symptoms. In sheep the ixodidie usually affix themselves at points 

 where the skin is tender and unprotected by wool, as for instance the 

 thighs, armpit, and upper part of the neck. Their bites produce irrita- 

 tion, followed by an intense burning sensation, and the formation of a 

 red blush round the point bitten. 



In the ox the ticks fasten on the neck, behind and within the ears, 

 and also wherever the skin is tender. Until the last few years little 

 importance was attached to their development, but since it has been 

 proved that Eltijncrphalu.s annalatas is the active factor in desseminating 

 Texas fever, ticks have attracted much attention. 



It seems, moreover, to be proved by the researches of Lignieres that 

 a form of piroplasmosis exists in France, and it seems possible that the 

 Ixodes ricinus may be a means of propagation. 



The diagnosis of acariasis produced by ticks is easy, for the para- 

 sites attain large dimensions. 



