Don R. Arthur Ticks

Annotation

Whilst the greatest effort has been made to ensure the quality of this text, due to the historical nature of this content, in some rare cases there may be minor issues with legibility. Various species of Dermacentor are of immense medical and economic importance to both man and his domestic stock, being recognised as vectors and reservoirs of bacilli, piroplasms, theilerias, Viruses and rickettsiae among others. Accordingly a number of species, particularly in the United States, have been treated as first priorities in disease control schemes. Our knowledge of the morphology and biology of these American species has been the result of extensive work, both in the field and laboratory, by such workers as Cooley, Kohls, Hooker, Bishopp and Smith to mention but a few. In Canada the importance of D. Andersoni as the causal agent of paralysis in both man and cattle provided the stimulus for Gregson's untiring pioneer work in this field and represents a wonderful example of scientific patience, exactitude and initiative. The situation in Europe and Asia is less well defined, but much credit is due to Cerny and his colleagues for their excellent contributions to our knowledge of D. Reticulatus and D. Marginatus. Possibly one of the major obstacles in the general evaluation of tick problems in Russia and the Far East has been the language difficulty.