66 



Observations on Parasites and Parasitic Diseases 



Our description of the Trichodectes Ovis will be found at page 

 46 et scq., and also an illustration of the epizoon, to which we 

 beg to refer the reader. 



Louse of the Pig. 



One variety only of the two kinds of lice, so frequently alluded 

 to in these pages, is met with on the pig, viz. the Hamatopinus 

 Suis. Subjoined is a magnified illustration of this epizoon, which 

 will help to convey an idea of its formidable appearance. 

 Its great size, broad and flat body, thick ungues, and dark brown 

 colour at once suffice to distinguish the HcBmatopinus of the 

 pig from that of any other animal. Most of these peculiarities 

 will be observable if the figure be compared with Fig. 8, which 

 represents its congener of the horse, both being drawn to the 

 same scale. 



Fig. 10. 



HcEinatopinns Suis. Magnified. 



On many farms these parasites are but rarely seen, while on 

 others they are of rather frequent occurrence. The cause of their 

 absence seems not to be well understood, as it does not appear 

 to depend on greater cleanliness nor on a better system of manage- 

 ment. Store pigs are mostly affected, but we have seen the lice 

 at times on fat ones. The use of barley-straw for bedding, as well 

 as its almost exclusive employment in the fodder-yard, is gene- 

 rally thought to encourage their attack. This idea is not impro- 



