^^■Dn^A Vol. 62, pp. 57-68 ^<JlfUP^/\l M\Jv^^i>^ April 27, 1949 PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON GEOGRAPHIC VARIATION IN THE RIBBED FROG, ASCAPHUS TRUEI By M. B. Mittleman and George S. Myers In the Pacific Northwest, from British Columbia and Mon-tana to northern California, occurs the most remarkable of North American frogs. Ascaphus triiei Stejneger is not only the most primitive New World frog, but it also possesses a tadpole unique among Nearctic Salientia. Heretofore, but a single named population has been recognized within the genus Ascaphus. While it is the primary purpose of this paper to demonstrate the existence of three recognizable popu-lations of Ascaphus, a brief historical and systematic intro-duction appears to be useful. The Ascaphidae, as recognized by Noble (1931: 485, where called Liopelmidae), include but two genera, Leiopelma and Ascaphus. The first-known genus, Leiopelma^, is restricted to New Zealand, from whence three forms have been described: L. hochstetteri Fitzinger, L. hamiltoni McCulloch, and L. arclieyi Turbott. The primitive nature of Leiopelma was not at first understood, principally because of the then-rudimentary state of frog classification. Fitzinger (1861) compares the genus with Telmatobius and Cyclorhamphus, two neotropical genera now referred to the Leptodactylidae. Steindachner (1867: 33) places Leiopelma in the **Bombinatoridae," a heterogeneous group assembled by Giinther, and based chiefiy on dentition, hympanum, and toe-webbing. Boulenger (1882: 447) appears to have been the first to recognize that Leiopelma belongs with the primitive, ribbed frogs, but his later denial of the presence of rudimentary ribs, and consequent placement of Leiopelma in the " Cystignathidae " (= Leptodactylidae), in 1910 (p. 150, foot-note), has never been properly explained. The work of Noble (1922) reinstated Leiopelma among the ribbed frogs, but he separated this genus and Ascaphus from the more advanced Discoglossidae, in which all the ribbed frogs had previously been placed (Noble, 1931: 485). On the other hand, Ascaphus, unlike Leiopelma, was recognized as a primitive frog from the very first. The unique type specimen was obtained by Cloudsley Eutter of Stanford University, during the course of some ichthyologieal work he was doing for the U. S. Fish Commission ^This generic name is spelled Liopelrna by most recent writers, following' Bou-lenger (1882: 447). Myers and Carvalho (1945: 17, footnote 5) called attention to this error, althoiigh they did not have Fitzinger' s original paper in hand. While the classically correct transliteration of the name would be Liopelrna, Fitzinger (1861: 218) spelled it Leiopelma, and the International Rules require the retention of tbis orthograpby. 13 — Pkoo. Biol.. Soc. "Wash., Vou 62, 1949 (57) AFR 28 1940
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