- 1. Distribution: A general map of distribution is given in the introduction, showing the range of the genus as a whole. A second, composite map, provides collection localities for the three species studied. Other maps indicate sites of collection for each individual species, including nests of P. longicaudus and P. silvicola, taken in Oregon. Due to the rarity of these mice and the limited localities from which they have been taken, no all-inclusive range boundaries
have been attempted. 2. Habitat and ecology: The habitat and ecology of these mice are singularly similar, as they are endemic to the humid areas of western Oregon and northern California. Information on P.
albipes is primarily from the literature. The data on P. silvicola is based upon field observation as is to some extent, that on P.
longicaudus. 3. Home range: The scarcity of animals, coupled with difficulty in collecting and field observations, has made a home range study impossible. 4. Nests: A compendium, as complete as possible, is presented on the published studies carried out in California on the nests of P. longicaudus. In Oregon, data were assembled from the careful examination and dissection of 150 nests, with supplementary information obtained through the literature. Nothing could be found pertaining to P. albipes.
5. Behavior: Field observations of 100 mice, plus limited laboratory observations, form the basis of the information in this study. Additional laboratory. observations are being made by Dr. Murray Johnson of Tacoma, Washington, to be compiled at a later date.
6. Food and water: Data on food and water were obtained in both the field and laboratory. 7. Breeding biology: Careful records were kept on pregnant females and young, caught during this study. Dr. Murray Johnson is doing the principal study on the breeding biology of P. silvicola. There exists minimal data on P. albipes. Information on P. longicaudus is primarily from the literature. 8. Molts and hibernation: The discussion of molts and hibernation is based on material from the literature. 9. Parasites: Parasites were collected from both mice and nests. Berlese funnels were used to get the parasites from the nest material, while those on the individual mice were picked off with a fine paint brush dipped in 70 percent isopropyl alcohol. These were given to experts for determination, 10. Mortality and economic status: Information was collected in the field and expanded from the literature. 11. Population: A thorough population study was conducted over a period of about two months. The area covered consisted of 30-2/3 acres of relatively uniform second growth Douglas fir. The entire area was systematically searched for nests. Each nest was identified, dissected, and recorded. Of the 41 mice known to be in the area, all but one was captured. A complete history of the area
is given, from 1900 to the present. Aerial and ground photographs, along with diagrams, are used for clarification. 12. Taxonomy: A thorough taxonomic study on the status of P. longicaudus and P. silvicola is being conducted by Dr. Murray Johnson. The status of P. aibipes appears to be undisputed.