46 Observations on Parasites and Parasitic Diseases 



Melophagi inconvenience sheep considerably ; but we have 

 never observed any special disease of the skin to be produced 

 by them. It is, however, imperatively necessary that they be got 

 rid of, not only for the comfort of the animal, but for the saving 

 of wool. During the winter few " ticks " are to be seen, but on 

 the approach of spring they begin to procreate with great rapidity, 

 so that by shearing-time many sheep, and especially hoggets, will 

 often swarm with them. They are somewhat erratic in their 

 habits, and will not only quickly travel from sheep to sheep, but 

 likewise on to shepherds and others who have the handling of 

 the animals. They, however, are never found to inflict any 

 injury on such persons, but merely to produce a good deal of 

 tickling of the skin over which they roam. Their instinct often 

 leads them to seek a hiding-place among the hairs of the head, 

 but even here they do not rest very long, not finding their proper 

 habitat. 



" Dipping" of sheep is the only effectual means of destroying 

 these parasites, and the earlier in the spring, weather permitting, 

 hoggets are dipped the better. By this means the destruc- 

 tion of a numerous progeny by the death of the parent Me- 

 lophagi is secured, and a corresponding advantage obtained both 

 for the comfort of the animal and the interest of the flock-master. 

 Not only are " ticks " and many pupae thus got rid of, but also 

 lice and acari, the latter of which are the immediate cause of the 

 disease known as scab. Various mixtures, more or less destructive 

 to parasites, are employed as baths for sheep, some of which can 

 scarcely be used with safety. Before, however, we speak of 

 these mixtures, we purpose to add some remarks on the louse 

 of the sheep, a parasite by no means so well known as the 

 " tick." 



Trichodectes Ovis. — Louse of the Sheep. 



This parasite is common in some districts but very rare 

 in others. Some very extensive flock-masters seem, indeed, to 

 be hardly aware of its existence, and in answer to our inquiries 

 have said that they had neither seen nor heard of it. It prevails 

 chiefly where periodical dipping is not adopted, and hence it is 

 often present in mountain-sheep and also in sheep imported 

 from Ireland. In many parts of the western counties of England 

 the Trichodectes is by no means rare, and farmers are in the 

 habit of using sulphuretted oil, and similar agents, two or three 

 times a year for its destruction. It is known in these districts 

 as the red louse of sheep ; its head and thorax being of an iron 

 colour, and its body a pale yellow, marked with dark bands. 



Denny, in his ' Anoplurorum Britannia?,' describes its chief 

 characteristics to be — " head, nearly orbicular ; clypeus rugulose 



