SEVENTH ANNUAL REPORT. 



129 



TRICHODECTES CERVUS : HAIRLING. 



dom made, since similar remedies are amply adequate when 

 thoroughly applied to destroy both alike. 



The particular significance of this outbreak lies in the fact 

 that these mites may at any time become epidemic, at least in the 

 deer family, while at range, whereas the pediculus or louse is 

 seldom or never known to become troublesome outside winter 

 quarters, where treatment may be easily and successfully carried 

 out. 



The hairling kills from general irritation rather than by reason 

 of living upon the blood and lymph of the host, as in the case 

 of the louse, being, as may easily be discerned from the accom- 

 panying micro-photograph, essentially constructed to fare di- 

 rectly upon the epidermal cells and hair structure ; hence the 

 name hairling. 



