British Honduras: Cayo: 6.2 km. S El Cayo, MCZ 37885-92. Stann Creek: Stann Creek, FMNH 49068.

Guatemala: Alta Verapaz: 28.3 km. N Campur, KU 64578-90; Chinajá, KU 57425; Cubilquitz, UMMZ 90887, 90888 (4); Finca Chamá, UMMZ 90879 (13), 90880 (4), 90881, 90882 (28), 90883 (12), 90884 (46), 90885 (39), 90886 (20); *Finca Tinaja, BYU 16032; Panzós, UMMZ 90889 (2). Chiquimula: Chiquimula, UMMZ 98113; 2 km. N Esquipulas, UMMZ 106844. El petén: La Libertad, KU 57447-97, 59907-11 (skeletons), MCZ 21461, UMMZ 75332 (13), 75333 (11), 75334 (14), 75335 (10); Piedras Negras, FMNH 113123, UIMNH 20966; *5 km. S Piedras Negras, USNM 114951-72; Tikal, UMMZ 117981 (2); Toocog, 15 km. SE La Libertad, KU 57426-46. El Quiché: Finca Tesoro, UMMZ 89165 (5). Huehuetenango: Finca San Rafael, 16 km. SE Barillas, FMNH 40917-9. Izabal: Puerto Barrios, FMNH 20004-7; 8 km. S Puerto Barrios, KU 57507-37, 59991 (eggs), 59992 (tadpoles); Quirigua, CAS 69657-701; 2.5 km. NE Río Blanco, KU 57539; San Felípe, FMNH 35065. Zacapa: 14 km. ENE Mayuelas, KU 57502-6; 8 km. ENE Río Hondo, KU 57498-501.

Honduras: Atlantidad: La Ceiba, UMMZ 91948 (2), USNM 117593-600; Lancetilla, MCZ 17981. Cortes: Lago Yojoa, AMNH 54917-9, 54957, 55134, KU 64563-77. El Paraiso: Valle de Jamastran, AMNH 54807-12. Francisco-Moranza: El Zamorano, AMNH 54873-81, KU 103223, UMMZ 123101; Montaña de Guaimaca, AMNH 54900-4 (8); Ranch San Diego, 19 km. SW Guaimaca, AMNH 53939. Itibucá: Vieja Itibucá, AMNH 54912-3.

Nicaragua: Chontales: 3 km. SW Santo Tomás, KU 64770-9, 68308 (skeleton). Esteli: Finca Venecia, 7 km. N, 16 km. E Condega, KU 85296; 2.4 km. N Estelí, MCZ 28933-7. MANAGUA: 12-13 km. E Managua, KU 85297-301; *10 km. SW Tipitapa, UMMZ 119977 (10). Matagalpa: *Finca Tepeyac, 10.5 km. N, 9 km. E Matagalpa, KU 85302-3; Hacienda La Cumplida, KU 64780-96, 68309-11 (skeletons), UMMZ 116482 (8), 116483 (23), 116484 (3), 116485 (5), 119984 (3). Rivas: *Finca Amayo, 13 km. S, 14 km. E Rivas, KU 85304-7; 16 km. S Rivas, MCZ 29011-7; *20.5 km. SE Rivas, KU 85308-10; 5 km. SE San Pablo, KU 43111-4.

Costa Rica: Guanacaste: Arenal, USC 6254 (2); *3 km. W Bagaces, USC 7019 (10); *3 km. NE Boca del Barranca, USC 8017 (21), *Finca San Bosco, USC 6272 (6), 6276 (3); *Guayabo de Bagaces, USC 7022 (4), 7023 (3), 7025; 12 km. S La Cruz, USC 8091 (2); *Laguna Arenal, USC 6262; *27 km. N Las Cañas, USC 8171 (6); *16 km. E Las Cañas, KU 102252-8; 16 km. SSE Las Cañas, KU 65090-5; *20 km. SE Las Cañas, KU 102251; Liberia, KU 30827-39; *7.3 km. N Liberia, USC 8096 (4); *10 km. N Liberia, USC 8085 (9); *7.5 km. SE Liberia, KU 65102-8, 68621-2 (skeletons); *14.7 km. S Liberia, USC 8238 (3); *4 km. W Liberia, KU 36847-57; 2 km. S Nicoya, USC 8230; *3-10 km. ESE Playa del Coco, USC 8012 (16), 8137 (14); *21.6 km. ESE Playa del Coco, USC 8138 (13); *Peñas Blancas, KU 102247-50; *Río Bebedero, 5 km. S Bebedero, KU 65089; *Río Higuerón, USC 7168 (2); Santa Cruz, USC 8232 (2); *Silencio, USC 6248; *Tenorio, KU 32313; Tilarán, KU 36858-60; *2 km. E Tilarán, KU 86403, *5 km. NE Tilarán, KU 36840-6 USC 6269. Puntarenas: Barranca, KU 32305-12, *5 km. WNW Barranca, UMMZ 119976 (2); *10 km. E Esparta, KU 86400-2; 1 km. WNW Esparta, KU 65101; *4 km. WNW Esparta, KU 65088; *10 km. WNW Esparta, KU 65063-87, 68616-20 (skeletons); *12 km. WNW Esparta, KU 65096-100, USC 8251; 21.8 km. W San Ramón, USC 8242 (15).

Hyla robertmertensi Taylor

Hyla robertmertensi Taylor, Proc. Biol. Soc. Washington, 50:43, April 21, 1937 [Holotype.—CNHM 100096 (formerly EHT-HMS 2270) from Tapachula, Chiapas, México; H. M. Smith and E. H. Taylor collectors]. Smith and Taylor, Bull. U. S. Natl. Mus., 194:84, June 17, 1948; Univ. Kansas Sci. Bull., 33:326, March 20, 1950. Mertens. Senckenbergiana, 33:170, June 15, 1952; Senckenbergischen Naturf. Gesell., 487:30, December 1, 1952. Stuart, Contr. Lab. Vert. Biol., Univ. Michigan, 68:47, November, 1954. Duellman, Univ. Kansas Publ., Mus. Nat. Hist., 13:63, August 16, 1960. Duellman and Hoyt, Copeia, 1961 (2): 417, December 19, 1961. Porter, Herpetologica, 18:168, October 17, 1962. Stuart, Misc. Publ. Mus. Zool., Univ. Michigan, 122:36, April 2, 1963. Duellman and Trueb, Univ. Kansas Publ., Mus. Nat. Hist., 17:348, July 14, 1966.

[Diagnosis.]—Brown lateral stripe wide, including loreal region and entire tympanum, extending to groin, bordered above by narrow white line; dorsum unicolor or with pair of dark lines (or rows of dashes) usually extending only to the sacral region; shanks having dark flecks, no transverse bars; interorbital bar lacking.

Description and Variation.—Males attain a maximum snout-vent length of 26.4 mm. in Oaxaca, whereas in a sample from Acacoyagua, Chiapas, the largest male has a snout-vent length of 25.7 mm., and from La Trinidad, Guatemala, 24-6 mm. Specimens from the western part of the range (eastern Oaxaca) have slightly smaller heads and proportionately larger tympani than the more eastern populations ([Table 1]).

The color pattern shows little variation, except in the nature of the dorsal markings. In a few specimens from throughout the range, but especially in the eastern part of the range, the dorsum lacks markings between the dorsolateral white lines. In most specimens the dorsal pattern consists of flecks or dashes arranged in two parallel longitudinal rows, and in some specimens the marks are fused into parallel lines. Small brown flecks are present on the dorsal surfaces of the shanks; in some specimens these flecks tend to form a longitudinal stripe on the shank. An interorbital dark mark is invariably absent.