Mites hijurious to Domestic Animals. 91 



have been found on rabbits, but little is known about tbe structure 

 or habits of this mite. 



Some of the mites of the genus Laelafs, C. L. Koch, are parasitic 

 on rodents, moles, and other small mammals. One species 

 (X. ecMdninus, Berlese, fig. 71) is parasitic on the brown rat and, 

 like its host, is probably cosmopolitan ; another species {L. nuttalli, 

 Hirst) is common both on the black rat and brown rat in 

 tropical regions. The species of HdciDOf/aiiiasiis, Berlese, suck the 



Fig. 7(i. 



Sternostomum rhynolethrum (p. 92). — Female from below. 

 (After Berlese.) 



blood of various small mammals such as moles, field mice, etc. ; 

 and one species (H. oudemansi, Hirst) is found on the brown rat in 

 this country. 



Genus Bntlliefia, Trouessart, 1902. 



Raillietia amis, Leidy, 1872. 



(Figs 72-74.) 



In general appearance this mite resembles a Dermanyssus or 



Lipomjssus. Second .leg of male very characteristic, being armed 



