Sept. 1895.] 



INJURIOUS INSECTS AND FUNGI. 



163 



to separate the mites obtained in Oregon, California, and 

 Montana, from those obtained from Central and Eastern States. 

 Another species, Bryohia pratensis, is found upon peach, apple, 

 and other trees in the United States. 



This Damson mite, Bryohia, belongs to the family of Tetrany- 

 chidce, and is found on the damson leaves as soon as they are 

 formed. Generation succeeds generation with rapidity. Larvae 

 of all sizes are seen upon the leaves and quantities of eggs, 

 generally fastened near to the midribs. At first, the globular egg 

 is whitish, but it gradually becomes crimson, and is dark red 

 before the larva is hatched. The larvae are red while they are 

 young, but become more of a brown, and in some cases a greenish- 

 brown colour, as they get older. In the first stage, the larva 

 has three pairs of legs. After the first moult there are four pairs 

 of legs of which the anterior pair are extremely long. The legs 

 have six joints, and at the ends of the tarsi there are four hairs 

 with knobs, and two hairs at the base without knobs. There 

 are peculiar scales arranged along the body of the mite, in 

 four pairs. From each of these a long spine, or bristle, extends. 

 There are also scales with hairs at intervals round the body. 

 The two eyes are placed far back upon the thorax, in the centre 

 of dark red spots. There is no web in connection with this 

 species. The larvae take refuge under the ribs of the leaves. 

 During the winter, the larvae may be found under the bark of 

 the damson trees and in the little tufts of mosses and lichens 

 upon the bark. Eggs can also be seen in the interstices of the 

 bark. 



Modes of Prevention and Remedies. 



When trees are infested, it is desirable to throw very finely 

 powdered lime over them in damp weather, in the late autumn, 

 or early spring, to kill the mosses and lichens which harbour 

 the mites and their eogs. Syringing the trees with a solution 

 of sulphate of iron at the rate of one pound of sulphate of iron 

 to one gallon of water also kills the mosses and lichens as well 

 as the mites where it reaches them. 



Infested trees should be syringed directly the blossom is well 

 set, with soft soap and quassia, put on with a fine jet, so that 

 every part of the leaves is sprayed. This will render the 

 leaves distasteful to the mites. Paris Green solution will make 

 the foliage poisonous to the mites, but it must not be used 

 stronger than at the rate of one pound to 275 gallons of water. 



Soft soap and petroleum, or kerosene oil, mixed well together, 

 is valuable. But it must be thoroughly incorporated. Kerosene 

 " emulsion " is made in America according to the following 

 formula : — 



Kerosene oil, six pints ; water, four pints ; soft soap three and 

 a quarter pounds. This is well mixed and diluted twenty-five 

 times with water and put on in a fine spray. 



