1910 ENTOMOLOGICAL SOCIETY. 83 



resemblance to Spiders and Scorpions in the Arachnida, and by the best authorities 

 have been put in one order of this class. 



However, in structure they are so unlike and in habits they are so varied that 

 one never loses interest in his researches. Perhaps one of the most interesting 

 features in the study of mites is shown in the manner in which they protect them- 

 selves against their enemies Uy special adaptations. The species belonging to the 

 genus Nothrus are found on the bark of spruce and pine and appear in colour 

 and shape like tiny bits of bark and lichen. A species of Analgesid, found on 

 the wings of the Baltimore Oriole, presents precisely the same shade as the 

 feathers of the wing. Tetranychus spinosa, which feeds in the upper surface of 

 the leaf of the basswood, is identically the same colour as the leaf, and the writer 

 found it impossible to detect the difference except by use of the microscope. 



In the Gall Mite family the young mites are almost as translucent as are the 

 trichomes, but when with age tliese trichomes turn brown and then black, the 

 mites also assume the same colours in the same manner. Any number of similar 

 examples might be mentioned if space permitted, but sufficient has been s^id to 

 indicate the adaptation of these animals to their colour environment. Another 

 species of Nothrus may be mentioned as demonstrating protection from dryness 

 and heat. In this case the mite accumulates a covering of dust upon its back. 

 Similarly at the approach of cold, the mite surrounds itself with particles of any 

 substance within reach. Further illustrations of adaptation to environment are 

 seen in a species of mite found upon the roots of Yarrow, with legs broadened, 

 mole-like, fitting it for digging and burrowing in the earth. In the genus Chey- 

 letus, the palpi are large and branched, fitted for grasping, and the mouth parts 

 are long and piercing, providing the mite with suitable weapons for a predaceous 

 life. Aquatic species are greatly modified forms of land mites, with flat and hairy 

 legs, enabling the mite to propel himself quite freely in the water. The parasitic 

 mites attacking all kind of animals have many special devices for attaching them- 

 selves to their host and adequate provision for obtaining nourishment from the 

 body of the victim. 



The curious shapes and odd looking appendages found in many of these 

 creatures appear to the observer to be more ornamental than useful. The bird 

 mites with their angular construction and long tail-like appendages afford the best 

 examples of this class. The sugar mite Glyciphagus with its fan-like attach- 

 ments is another instance of apparently useless equipment. 



In richness of colour and beauty of marking, the Tetranychids and Analgesids 

 are most noticeable. Indeed, some of these handsome species are worthy of the 

 attention of any one interested in the field of Nature. Am,ong the most remark- 

 able phases of animal architecture are the abnormal constructions of vegetable 

 tissues produced by species belonging to the family Eriophyidfe. About seventy 

 different species of these worm-like creatures inhabit trees, shrubs and herbs of 

 Ontario flora. 



Not the least wonderful of the habits exhibited by the Acarids are their modes 

 of distribution. As will be shown in our discussion of the dung beetles, many 

 species of the scavenger mites make use of dung beetles and flies to bear them to 

 new feeding grounds. A few species are specially provided with a cord, secreted 

 by glands in the body, by means of which they fasten themselves to their carriers. 



Another interesting feature in this connection is their friendship to other 

 animals, a few species sharing the home of many of the common species of ants. 

 Here we find the ants repaid for their hospitality to the homeless mites by having 



