7 8 OTHER ITCH-MITES. 



etc., should be carefully disinfected. The ears of the affected 

 dogs have to be kept clean, the dark substance found must 

 be removed, and one or the other of the following mixtures 

 should be injected. 



Olive-oil 100 grammes 



Naphthol 10 



Ether 30 



Some of this fluid, which has to be kept in a well-stop- 

 pered bottle, should be injected every day into the external 

 auditory canal, which is then closed for ten or fifteen minutes 

 by a cotton plug to prevent the evaporation of the ether. 



A mixture of one ounce of olive-oil with one drachm of 

 ointment of the nitrate of mercury, daily painted over the 

 internal surface of the ear with a soft brush, has also answered 

 the purpose. After a week the ear should be syringed out 

 with tepid water and methylated spirit, about one to ten. 



The same or a very similar parasite has been found in 

 the ear of the cat, where it causes extraordinary symptoms, 

 the animal being almost unable to walk ; in fact, when it at- 

 tempts to do so it rolls about as if intoxicated, frequently 

 falling over on its side. 



The ferret, which in many places is kept as a domesti- 

 cated animal, is also aftected by this or a very similar par- 

 asite. 



The Itch-mites contain, besides those already de- 

 scribed, a number of other small mites which infest birds. 

 Such mites are found upon nearly all birds, and whoever 

 searches for them will discover new and most remarkable 

 forms. The two forms, male and female, shown in fig. 43 and 

 44, were found with others of a still different shape upon the 

 Purple Grackle. Some of these mites are really beautiful ob- 

 jects, which pass through wonderful and most complex 

 metamorphoses. Many torment their hosts, while others 

 simply dwell upon them without causing any apparent dis- 

 turbance or injur3^ In some cases each species inhabits only 

 one kind of host, even a certain part of it, while others seem 

 to care but little where they dwell providing the host is a 

 bird. Every bird possesses one or more of such parasites, 

 and cases are known where one bird gave a home to four 



