IXODIDA. 61 



boscis, during whicli, by unceasing sucking, their >flat form 

 becomes globular, and ten to twenty times its original size. If 

 they be torn away with violence, the head easily remains sticking, 

 by which inflammation, pain, and suppuration, lasting even for 

 months, are produced ; for this reason it is always advisable to 

 compel them to loosen themselves. 



Therapeutics. The only indication is to cause the voluntary 

 detachment of the animal. For this purpose Ok en advised the 

 dropping of a drop of olive oil upon them. But they do not always 

 let go their hold after this. Ratzeburg recommends rubbing the 

 animal constantly with the oiled finger, for which a quarter to 

 half an hour is often required. In his ' Illustrated Natural 

 History/ Poppig recommends touching them with tobacco oil, oil 

 of turpentine, or mercurial ointment. The last is superfluous. 

 The oils just mentioned are certainly sufficient, or still better the 

 essential oils, such as oil of anise or rosemary. I would, how- 

 ever, not merely touch the back of the animal, but rather in 

 preference rub its ventral surface with a feather dipped in the oil, 

 so as to come as near as possible to the respiratory opening on the 

 belly, and poison the animal as quickly as possible. 



The tick often mentioned as the Argas Persicus, or the poison- 

 bug of Miana, may also be referred to here. As what has been 

 narrated of it and its dangerous nature is mere fable, and the 

 natives take it into their hands quietly and without danger, I 

 shall only treat of it here en passant. Its bite, like that of all 

 Ixodida, probably causes considerable pain, and if the head be torn 

 off and left sticking in the wound, it may also produce malignant 

 sores. But everything is fable. The bad consequences com- 

 monly ascribed to it, agree with the symptoms of the putrid fevers 

 which prevail in hot climates, often endemically in small districts, 

 and carry off more especially foreigners who have not become 

 acclimatised, whence it is probable the opinion has arisen that the 

 mite only injures foreigners. 



The Argades are distinguished from Ixodes by their having a 

 small head, seated on the under side of the fore part of the body, 

 a very short proboscis, and three-jointed, conical palpi. The 

 Argas Persicus } which only occurs in Persia, is characterised by 

 the small, white points which extend over the whole back, and are 

 the more striking upon its light blood-red colour, because it is 

 usually larger than the wood-tick (namely 3'"), and has the 

 anterior legs directed forwards as raptorial arms. 



