BEETLE MITES. 



223 



insect not shut up ; 26. Ditto contracted. All copied from figures by 

 Claparede, in Zejtsch. fiir Wiss. Zool. xviii. 



ITopIrphora contractilis. Ditto, .■-hut up. 



perffC- insect, not siiut up. Copied from Claparede. 



Claw of ditto. 

 Copied from Clapariide. 



M. Claparede of Geneva, not long before his death, made a 

 series of studies of the Acaridae, one result of which was to reveal an 

 affinity between the Oribatidte and the Acarids proper (cheese mite 

 tribe), which, if suspected, had, at all events, not been previously 

 tistablished. The older writers, Gervais for example, instinctively, 

 perhaps, felt that it was so, and so arranged them ; but in the 

 most recent handbooks (such as those of Gerstaecker and Glaus), 

 the GamasidjB and Ixodid^ are placed between the Oribatidse and 

 the Acarids proper, but Glaparede has given good reasons for 

 regarding this as an unnatural arrangement. The arrangement 

 of Gervais was better. He placed the Acarids next the Ixodidse, 

 and the Oribatidae last ; but we wish to close the arrangement of 

 the mites with the parasitic Sarcoptidse as a passage to the lice, 

 and therefore place the Oribatidse before the Acarids instead of 

 after them, it being indifferent so far as any other affinity is 

 concerned^ where we place them. The present species was the 

 medium which led Claparede to these conclusions. It lives in 

 moist and decaying fir wood, burrowing in and feeding on the 

 wood, the burrows for the most part running parallel with the 

 vessels of the Avood, but also occasionally running into one another. 

 Its habits thus give some facility for observation. A morsel of 

 v/ood inhabited by them could be put in a glass tube and kept at 

 the proper degree of moisture, while their development is being 

 watched. The perfect mite is very minute, clothed with a thick, 

 hard, rigid, brown coat of mail, and with a curious power of 



