748 



The Bulb Mite. 



[march, 



the varieties supplied became their property. These stations are 

 inspected and reported upon annually. In this way valuable in- 

 formation has been obtained as to the merits of different varieties 

 of fruit, the soils to which they are adapted, and the climatic 

 conditions under which they may be expected to thrive. Model 

 orchards have also been established in Quebec, the trees being 

 supplied by the Department of Agriculture to farmers in certain 

 localities, who undertake to plant and manage them according 

 to the directions of the Department. 



Rhizoglyphus is a genus of Mites belonging to the family 

 Tyroglyphidce, a family with a comparatively small number of 



a species which has several times been found swarming over 

 furniture, curtains, &c, in houses. The family is interesting bio- 

 logically, as amongst its members we get, in addition to the 

 stages in the life-history of mites in general, the hypopus stage, 

 this being a stage developed for the purpose of the spread of 

 the species. Besides other differences, it is characteristic of the 

 hypopus that it possesses suckers by which it can adhere to 

 flying or passing animals, and thus be conveyed to fresh feeding 

 grounds. In this stage the mite is able to resist conditions which 

 would be fatal to it in its other stages. All the individuals of the 

 same generation do not pass through this hypopial stage. 



There are two British species of Rhizoglyphus, viz., the Bulb 

 Mite (R. echinopus) and R. agilis. The latter, discovered by 

 Michael on decaying cabbage stalks in the South of England, is 

 narrower in body, lighter in colour, and more active in habit 

 than the Bulb Mite. 



Food Plants of the Bulb Mite. — Rhizoglyphus (root eater) 

 echinopus (spiny legs) feeds on underground swollen stems and 

 roots, e.g., the bulbs of the tulip, lily, hyacinth, onion, eucharis, 

 and the tubers of the potato and dahlia ; it has also been taken 

 in destructive numbers on the roots of the vine. This mite has 

 been distributed all over the world in its food plants. Signs of 



The Bulb Mite 



(Rhizoglyphus 

 echinopus). 



genera and species, but a great number of 

 individuals, masses of which may be found 

 together. Familiar examples of the family 

 are the cheese mites, the hay mites, and 



