196 



JOHN D. TOTHILL. 



mites, Bdella brevitarsis Banks (fig. 7), easily recognized by the snout-like beak and 

 geniculate palpi. A few specimens of a fourth, more hairy, coloured mite of about 

 the same size as the two preceding, were found hibernating under old scales at Covey 

 HilL This species is a Galumna. 





Fig. 6. Nymph of Gamasus sp., 

 which sometimes hibernates under 

 mussel scales. (Original.) 



Fig. 7. Dorsal view of Bdella brevi- 



larsus, Banks, a mite that sometimes 



hibernates under mussel scales. 



(Original.) 



Though examination of more material would undoubtedly reveal still other species 

 of mites using the convenient empty scales for winter shelter, none of these coloured 

 mites seem to have more to do with the control than did a budworm larva safely 

 housed for the winter in one of the old scales. At any rate there are no positive 

 data that any of these mites, or the additional ones mentioned by Ewing and Webster 

 (I.e. p. 129), ever feed on the oyster-shell scale. 



In a word, then, of these half-dozen mites the red and brownish species use old 

 scales for hibernation and are probably not factors in control. Of the uncoloured 

 or whitish species more closely associated with this scale, one, Monieziella, is a 

 scavenger and the other, Hemisarcoptes, a true predator on both eggs and adults. 



