On the Life-History and Habits of Rhizophagus 
depressus, Fowler.- 
BY 
R. STEWART MACDOUGALL, M.A,, D.Sc. 
With Figures 15-17. 
In addition to the family Nitulidae to which our beetle 
belongs, there are several related families which number 
amongst them species which live below the bark of trees in 
the galleries made by the bark-boring beetles. The members 
of these families, so found, prey upon the insect enemies of 
the trees. . 
Professor Nitsche' mentions the families and some of the 
useful forestral species which have been noticed by different 
observers. F ollowing Nitsche, and noting others from the 
literature, | summarise the families in tabular form, adding 
the name of the tree and the name of the pest infesting it. 
[TABLE 
{Notes, R.B.G., Edin, No, IIL, rg00.] 
