Haemaphysalis (Kaiseriana) davisi sp. n. is described from field-collected adults and nymphs, and from adults reared in the laboratory from nymphs. Samples were taken in tropical and temperate areas between approximately 470 and 9,000 ft altitude in Burma, Sikkim, and the NorthEast Frontier Agency (NEFA) of India. Recorded hosts of adults are the sambar deer, Indian muntjac or barking deer, gaur or Indian bison, tiger, hog badger, and domestic cattle, sheep, goats, horses, mules, and hybrids between cattle and gaur. Nymphs were taken from the sambar deer, muntjac, and gaur, and from most of the same domestic animals. H. (K.) davisi sp. n. is an easily recognized, large member of the H. (K.) bispinosa group. Haemnaphysalis (Kaiseriana) davisi sp. n. is described from field-collected adults and nymphs, and from adults reared in the laboratory from nymphs. Samples were taken from domestic and wild mammals and vegetation in tropical and temperate zones near Myitkyina (type locality) in Burma, the NorthEast Frontier Agency (NEFA) of India, and Sikkim. This distinctive large member of the H. (K.) bispinosa group is dedicated to our good friend, Dr. Gordon E. Davis, who collected most of the material recorded from Burma and who contributed so much to knowledge of tick-borne diseases during his career at the Rocky Mountain Laboratory. Haemaphysalis (Kaiseriana) davisi sp. n. Davis' bispined haemaphysalid (Figs. 1-28) Haemaphysalis neumanni Donitz, 1905. References to "H. neumanni" in India by Dhanda and Received for publication 5 March 1970. * From Research Project Number MF12.524.0093010, Bureau of Medicine and Surgery, Department of the Navy, Washington, D. C. The opinions and assertions contained herein are the private ones of the authors and are not to be construed as official or as reflecting the views of the Department of the Navy or of the naval service at large. The illustrations in this report were prepared under the auspices of Agreement 03-005-01 between the NIAID (NIH) and