192 



ARACHNOIDEA, 



CASE along with it a bundle of hairs, and then disclosed a small ulcer. 

 At the bottom of that ulcer, and completely concealed by the 

 crust, the parasite was found, and it was clearly the determining 

 cause of the pustule, because it healed up spontaneously as soon 

 as the insect was removed ; but as it would have taken too long 

 to destroy all the individuals one by one in this manner, they were 

 disposed of e7i viasse^ by lotions of an infusion of tobacco. Eight 

 days after its appearance, the malady, thanks to this treatment, 

 completely disappeared, leaving in the place of each pustule a 

 small smooth white scar." 



Previous to M. Megnin's publication, M. Lucas had given a 

 preliminary notice of the inatter to the Entomological Society of 

 France, from M. Megnin's information, and stated that M. 

 Megnin proposed for the insect the name I. pustularum, but he 

 gave no description. M. Megnin would appear to have forgot 

 this, and gave it the above name when he described it. 



Nos. Ixodes marginatus (Leach) (testudinarius, Murr.). — 7. Enlarged figure of 

 ^'10'.^' male; 8. Specimen of ditto (8); 9. Enlarged figure of female; 10. 



Specimen of ditto. 



Ixodes marginatus (male). 

 i\ lines in length. 



Ditto (female) unfilled. 



We beheve that this is the I. marginatus of Leach. The Ixodes 

 inarginatus of Fabricius is said to be Argas reflexus. 



It also is a British species, and sometimes has swarmed in such 

 great numbers on lawns and hay-fields, as to have made the 



