Probably the best solution for the problem of conservation of wild animals is the establishment of wildlife refuges. In Tamaulipas, at least three refuges are needed in order to preserve the mammalian wildlife. These areas would serve also as a refuge for game birds and other vertebrates. A large area with suitable habitat for white-tailed deer, brocket, jaguar, puma, javalin, and fox could be established in the Sierra de Tamaulipas, which presents favorable habitat for all of the species named. A second area that does not need to be so large as the first could be established in the Sierra Madre Oriental, probably including some part of Nuevo León, where the black bear and the mule deer find suitable habitat. Probably the beaver can be introduced in the streams of the high mountains; beaver live in the same Sierra a little farther north in Nuevo León. The three species mentioned are in imminent danger of disappearing from Tamaulipas, if they have not already disappeared. The third refuge could be in some area of the northern part of the state near the Río Grande. This refuge should give protection to the beaver--a rare animal in México and in danger of extirpation over all the country. The pronghorn also would find suitable habitat in this area, but would have to be reintroduced there. With the establishment of these three refuges and with good management the fauna of Tamaulipas could be saved from extinction, would provide some recreation for sportsmen, and especially for the people in general who wish to study, photograph, or merely observe the native animal life. The time is excellent for the establishment of the wildlife refuges in Tamaulipas because large areas are still in Federal ownership and because a considerable number of animals remain. Other favorable factors are that roads are not yet good in the areas proposed for refuges, the human population is low, and agriculture consequently is not practiced. But, with the rapid increase in population in México, these favorable conditions will change in a few years and it will be almost impossible to establish the refuges then. METHODS AND ACKNOWLEDGMENTS The families, genera, and species recorded in this report are arranged following Hall and Kelson (1959). Subspecies are in alphabetical order under the species. Remarks are given on natural history in each species account, if information is available. Discussion of subspecies known from the state is included. Under each subspecies, the citation to the original description is given with mention of type locality. Next is the citation to the first usage of the current name-combination. Then, synonyms are listed if there be such in the sense that original descriptions of the alleged species or subspecies had type localities in Tamaulipas.