MITES AND TICKS. 



2 45 



DOG- Oil SHEEP-TICK 



(enlarged). 



exclusively upon their hosts; they also occur on the ground, and under stones, 

 where pairing and the hatching of the eggs take place. When in want of food, 

 both old and young climb the stalks of grass and shrubs, and clasping the tips 

 of the leaves with their fore-limbs, stand with the other legs stretched out behind, 

 ready to catch the hairy skin of cattle as they sweep through 

 the herbage. Also belonging to this family are the genus 

 Argas and its allies, the species of which nearly equal the 

 larger Ixodes in size, and although much less numerous in 

 species and individuals have almost as extended a distribution. 

 They may be at once distinguished from the latter by their 

 coarsely granular skin, flattish bodies, and the entire conceal- 

 ment of the capitulum beneath the projecting fore-margin of 

 the cephalothorax. The species here figured (Argas reflexus) 

 is habitually parasitic on pigeons, and occasionally occurs in 

 England in places where these birds abound. A closely allied 



form from Persia — where it is known as the poisonous bug of Miana — is much dreaded 

 by the natives, its bite being said to produce convulsions, delirium, or even death. 



The next family (Ori- 



batidce) — the members of 

 which are sometimes called 

 beetle - mites, on account of 

 their hard and horny integu- 

 ment — contains a number of 

 species found for the most 

 part under the bark of trees 

 or in damp spots on the 

 ground, where they live by 

 sucking the juices of plants 

 and minute animals. The 

 palpi are free and tactile, the 

 mandibles pincer-like, and the 

 tracheae, when present, open in the socket of the last pair of legs. The last family 

 of true mites is that of the Sarcoptidce, which are either free or parasitic. They 

 have no special breathing-organs ; the palpi are basally fused to the rostrum, the 

 mandibles are pincer-like, and the tarsi are often furnished at their tips with a 

 sucker. The most familiar of those that are not parasitic 

 are the species known as cheese-mites (Tyroglyphus), which 

 feed upon decaying organic matter. The common cheese- 

 mite (T. siro), which has the body armed with rows of 

 long stiff bristles, is also found in flour and linseed meal. 

 Another allied species (T. entomophagus) frequently causes 

 much havoc among insect -collections, entirely destroying 

 the specimens if left unmolested, its presence in the cabinet 

 being usually betrayed by the fine dust that results from 

 its depredations. The most satisfactory method of destroy- 



1 J J CHEESE-MITE (much 



ing it seems to be soaking the cork of the box and the enlarged). 



pigeon-tick, from above and below (much enlarged). 



