186 



JOHN D. TOTHILL. 



rose-breasted grosbeaks eating oyster-shell scales off the apple trees near Eagle Rock 

 below Welsford. Some of the limbs were being cleared of them entirely. This was 

 in the winter of 1913-14." 



Insects. Coccinelhd^beetles or their larvae are known to feed on oyster-shell eggs, 

 but the number destroyed in this way in Eastern Canada, where the chief predator 

 is a mite, is probably almost negligible. 



Mites. The mite, Hemisarcoptes malus, Shimer (fig. 2), which attacks the eggs, 

 though apparently of European origin, was first discovered in Ohio in 1868 and 

 described by Shimer (Trans. Amer. Ent. Soc, v, pt. 1., 1868, pp. 361-374) as Acarus 

 malus. This author made a careful study of the habits of this mite and clearly 

 recognized its importance in the control of the scale. In the same year Walsh spoke 

 of the usefulness of what was probably this mite in Illinois (First Rept. State Ent. 111. ). 



Fig. 3. Moneziella angusta, Banks, ventral 

 view ; a scavenging mite liable to be confused 

 with Hemisarooptes ; a, dorsal view of bead ; 

 b, lateral view of jaw or cbelicera. (Original.) 



Of a number of subsequent records of mites feeding on oyster-shell scale I shall 

 refer only to some of the more important. Of 844 female scales examined by Le Baron 

 in 1870 from Kane and Du Page counties, Illinois, the contents of 254 were found 

 to be " destroyed by Acarids and unknown causes." Riley in his Fifth Report 

 figures a mite that he found feeding on both the eggs and adults of the oyster-shell. 

 In 1881 William Saunders (Canad. Ent. 1881) speaks of " a North American mite 

 which is a friend to the fruit-grower since it destroys the eggs of the oyster-shell 

 bark-louse." The species figured however is the scavenger Monieziella (fig. 3) that 



