24. Ascidians of the Littoral Zone of Southern California, by William E. Ritter and Ruth A. Forsyth. Pp. 439-512, plates 38-46. August, 1917 1.00 Index in preparation. Vol. 17. 1. Diagnoses of Seven New Mammals from East-Central California, by Joseph Grinnell and Tracy I. Storer. Pp. 1-8. 2. A New Bat of the Genus _Myotis_ from the High Sierra Nevada of California, by Hilda Wood Grinnell. Pp. 9-10. Nos. 1 and 2-in one cover. August, 1916 .10 3. _Spelerpes platycephalus_, a New Alpine Salamander from the Yosemite National Park, California, by Charles Lewis Camp. Pp. 11-14. September, 1916 .05 4. A New Spermophile from the San Joaquin Valley, California, with Notes on _Ammospermophilus nelsoni nelsoni_ Merriam, by Walter P. Taylor. Pp. 15-20, 1 figure in text. October, 1916 .05 5. Habits and Food of the Roadrunner in California, by Harold C. Bryant. Pp. 21-58, plates 1-4, 2 figures in text. October, 1916 .35 6. Description of _Bufo canorus_, a New Toad from the Yosemite National Park, by Charles Lewis Camp. Pp. 59-62, 4 figures in text. November, 1916 .05 7. The Subspecies of _Sceloporus occidentalis_, with Description of a New Form from the Sierra Nevada and Systematic Notes on Other California Lizards, by Charles Lewis Camp. Pp. 63-74. December, 1916 .10 8. Osteological Relationships of Three Species of Beavers, by F. Harvey Holden. Pp. 75-114, plates 5-12, 18 text figures. March, 1917 .40 9. Notes on the Systematic Status of the Toads and Frogs of California, by Charles Lewis Camp. Pp. 115-125, 3 text figures. February, 1917 .10 10. A Distributional List of the Amphibians and Reptiles of California, by Joseph Grinnell and Charles Lewis Camp. Pp. 127-208. 14 figures in text. July, 1917 .35 11. A Study of the Races of the White-Fronted Goose (_Anser albifrons_) Occurring in California, by H. S. Swarth and Harold C. Bryant. Pp. 209-222, 2 figures in text, plate 13. October, 1917 .15 12. A Synopsis of the Bats of California, by Hilda Wood Grinnell. Pp. 223-404, plates 14-24, 24 text figures. January 31, 1918 2.00