^4 



Gemld F. Hill 



Summary and Observations. 



The foregoing Experiments may be summarised as follows 



KxperiiiK'iit. 



All tilt' 



Louse-flies 



dead iti 





Class A. 



(Mass H. 



Class C. 





(Unfed ; 

 under 1 

 day old). 



(Fed ; 



;{-7 davs 



old).' 



(Adults) 



Season 



Da,vs. 



Days. 



Days. 





11 



12 



12 



Winter 



6 



7 



<> 



,. 



(a)(3 



8 



10 



,. 



(b)4. 



— 



— 



,. 



]4 



9 



12 



,, 



5 



(b)5 



K) 



,, 



— 



(c)7 



— 



., 



7 



12 



12 



,, 



1 



4 



(c)2 



,, 



— 



— 



(d)2 



>» 



2 



1 



(c)2 



,, 



— 



— 



(d)2 



" 



7 



(b)7 



10 



„ 



— • 



(c)9 



— 



„ 



(a)7 



8 



(f)9 



,, 



— 



— 



(d)5 



Spring 



— 



— 



(e).-) 



., 



(b)8 



— 



— 



Siinnner 



:4 



14 



18 



Winter 



s 



lU 



(c)ll 



., 



— 



— 



(d)0 



Spring 



9 

 10 



11 

 12 



18. 

 14. 



-Lawn grass in celllar - - - - 

 Lawn grass on Isiwn . - . . 

 -Soil with leaves on surface on lawn 



-As above. In cellar - - - - 

 -Soil without leaves on surface on lawn 



-As above in cellar . - . - 



-Wool on laboratory table - - ^ 



-As above. In cellar . - - . 



-Box of sheep-pen sweepings in sheep 

 shelter 



15.- On natural surface of sheep-yard 



IG. — Tree-trunk in cellar - - . - 

 17. — As above on lawn . - - . 



.18. — Jar of sheep-pen sweepings in sheep 

 shelter ------ 



18 



These experiments shov,' conelusivelv that the period of viability 

 of Melophagus ovinus, the so-called " sheep-tick," when removed 

 from the host is longer than has been generally believed. Curtice 

 (1890, p. 41) found that moderately Avell fed *' ticks " placed in a 

 ■cotton-stoppered bottle, with some wool, and kept in a room with a 

 temperature, vaiying between 6()°F. and 80° F. all died in less than 

 four days. Other " ticks " placed in wool over damp soil in a 

 flower pot died within the same period. Some younig ** ticks," which 

 he fed on the back of his hand wei-e kept alivje for nearly two weeks, 

 or until their daily feeding was neglected. 



