Chapter III: Part 3

_Remarks._--The identity of Cope's _Hyla puma_ has not been known. The name has appeared in various compilations, but no workers have referred any of their specimens to that species. Examination of the holotype (USNM 13735), an adult female, revealed the presence of the following combination of characters: snout-vent length 45.8 mm., snout blunt above and rounded laterally, nostrils close to tip of snout, lips thin and flaring, a vestige of a web on the hands, feet about one-half webbed, tarsal fold weak and extending about two-thirds length of tarsus, dorsal markings consisting of a faded dark interorbital bar and a pair of faded longitudinal brown marks connected by a transverse band in the scapular region. The type agrees well with specimens of _Smilisca wellmanorum_ (Taylor, 1952); the vestigial webbing on the hands and the dorsal coloration are especially significant. Consequently, we consider _Hyla wellmanorum_ Taylor, 1952, to be a synonym of _Hyla puma_ Cope, 1885. Cope gave only "Nicaragua" as the locality for _Hyla puma_. The specimen was part of a collection received at the United States National Museum from Lt. J. F. Moser. Among the species in the collection are _Dentrobates pumilio_, _Phyllomedusa helenae_, _Corythophanes cristatus_, _Pliocercus dimidatus_, _Tretanorhinus nigroluteus_, and others characteristically found on the Caribbean lowlands of Central America. Thus, it seems reasonable to assume that the type specimen of _Hyla puma_ came from the Caribbean lowlands. Though no other Nicaraguan specimens have been found by us, numerous specimens are known from the Caribbean lowlands of Costa Rica.

Cochran (1961:58), in her catalogue of type specimens in the United States National Museum, listed _Hyla puma_ Cope, 1885, as a synonym of _Hyla molitor_ Schmidt, 1857. She made no qualifying statements. Schmidt (1858:246), in his descriptions of the species in the year following his publication of the names and Latin diagnoses, stated: "Dorsum uniformly gray, more intensive on back, fading away laterally and on extremities; in every-day-life this blue would be called _Mueller's Blau_. A delicately dotted black line runs on the canthus rostralis from the opening of the nose to the corner of the eye. In the armpits, on the flanks and the thighs two of our three specimens have black marblings." [Free translation] Certainly on the basis of coloration _Hyla puma_ is distinctly different from _Hyla molitor_.

_Distribution._--This species lives in the wet, forested regions of the Caribbean lowlands of Costa Rica and presumably southern Nicaragua (Fig. 3). All specimens are from low elevations; the highest known elevation for the occurrence of this frog is 285 meters at Laguna Bonilla.

_Specimens examined._--62, as follows: NICARAGUA: No specific locality, USNM 13735.

COSTA RICA: =Alajuela=: Jabillos, 5 km. N Santa Clara, USC 8058 (6); 5 km. W La Fortuna, USC 8078 (2); Rio La Fortuna at La Fortuna, USC 7151 (3). =Cartago=: Laguna Bonilla, tunnel camp near Peralta, KU 32171. =Heredia=: Puerto Viejo, KU 86521; 5.9 km. W Puerto Viejo, KU 64307; 7.5 km. W Puerto Viejo, KU 64308-10, 64311 (skeleton), 64312-15, 68635-6 (skeletons), 85001-2 (skeletons), 86520, 87770-1 (skeletons), 91709-16, 91791-2, 91807 (tadpoles), 91808 (young). =Limon=: Batan, KU 30300-2; La Lola, KU 32169, USC 141, 201, 8067; Los Diamantes, KU 32170, UMMZ 118470 (6), USC 212; 2.4 km. E Los Diamantes, USC 8049 (5).

=Smilisca sila= new species

_Hyla gabbi_, Noble, Proc. Biol. Soc. Washington, 37:66, Feb. 21,
1924. Dunn, Occas. Papers Boston Soc. Nat. Hist., 5:413, Oct. 10,
1931. Schmidt, Smithsonian Misc. Coll., 89(1):6, March 16, 1933.

_Hyla sordida_, Dunn, Copeia, 3:166, Nov. 19, 1937. Cooper, Copeia,
2:121, June 30, 1944. Breder, Bull. Amer. Mus. Nat. Hist.,
86(8):417, Aug. 26, 1946.

_Hyla phaeota_, Breder, Bull. Amer. Mus. Nat. Hist., 86(8): pl. 55,
Aug. 26, 1946.

_Holotype._--Adult male, KU 91852 from a small stream at the north edge of the village of El Volcan, Chiriqui Province, Panama, elevation 1280 meters; obtained on Feb. 5, 1965, by William E. Duellman.

_Paratypes._--KU 91853-74, collected with the holotype.

_Diagnosis._--Size moderate ([M] 45.0 mm., [F] 62.2 mm.); skull wider than long, having large, ovoid frontoparietal fontanelle; supraorbital flanges absent; squamosal small, not contacting maxillary; bony section of ethmoid extending anteriorly between nasals; tarsal fold weak, full length of tarsus; inner metatarsal tubercle low, flat, elliptical; lips thick, rounded, not flaring; fingers one-third webbed; toes three-fourths webbed; diameter of tympanum about one-half that of eye; margin of upper lip faintly marked by interrupted creamy white stripe; dark spots on dorsum; pale flecks on flanks and posterior surfaces of thighs; vocal sacs in breeding males dark brown. (Foregoing combination of characters distinguishing _S. sila_ from any other species in genus.)

_Description of holotype._--Snout-vent length 36.6 mm.; tibia length 19.8 mm., 54.1 per cent of snout-vent length; foot length 15.5 mm., 42.3 per cent of snout-vent length; head length 12.7 mm., 34.7 per cent of snout-vent length; head width 13.3 mm., 36.8 per cent of snout-vent length; snout short, in lateral profile truncate, only slightly rounded above, in dorsal profile rounded; canthus rounded; loreal region noticeably concave; lips thick, rounded, not flaring; nostrils not protuberant, directed laterally; internarial distance 3.0 mm.; internarial area flat; top of head flat; interorbital distance 3.5 mm., 26.3 per cent of head width; diameter of eye 4.2 mm., thrice distance (1.4 mm.) from tympanum to eye, and half again distance (2.8 mm.) from orbit to nostril; pupil horizontally ovoid; width of eyelid 2.8 mm., 21.1 per cent of head width; dermal fold from posterior corner of orbit covering upper edge of tympanum to point above insertion of forelimb; diameter of tympanum 2.3 mm., 54.7 per cent of diameter of eye; no axillary membrane; arms moderately robust; weak fold on wrist; faintly scalloped fold along ventrolateral margin of forearm; fingers short, slender; fingers from shortest to longest, 1-2-4-3; vestige of web between first and second fingers; others about two-fifths webbed; discs moderate, diameter of that on third finger about one-third diameter of eye; triangular outer palmar tubercle; elliptical inner palmar tubercle on base of pollex; subarticular tubercles large, conical, none bifid; supernumerary tubercles few, large, conical; brown nuptial excrescence on prepollex; heels overlap by about one-fifth length of shank when hind limbs adpressed; tibiotarsal articulation extending to nostril; tarsal fold weak, extending nearly full length of tarsus; inner metatarsal tubercle elliptical, flat; outer metatarsal tubercle absent; toes moderately long; toes from shortest to longest, 1-2-3-5-4, third and fifth about equal in length; discs about same size as those on fingers; webbing extending to middle of penultimate phalanx on all toes, except only to distal end of antepenultimate phalanx of fourth toe; subarticular tubercles round; supernumerary tubercles large, round, present only on proximal digits. Anal opening directed posteriorly at level of upper edge of thighs; no noticeable anal sheath; flat tubercles ventrolateral to anal opening large; skin of chest, belly, and posterior surfaces of thighs granular; other surfaces smooth; tongue broadly cordiform, shallowly notched posteriorly, and barely free behind; vomerine teeth 4-4, situated on ventral surfaces of separated rounded prominences between posterior margins of small, ovoid inner nares; vocal slits long, each situated along inner margin of ramus; color (in preservative) pinkish tan above with irregular olive-brown markings forming interconnected spots on back; four bars on dorsal surface of each thigh; five bars on shank, and three on tarsus; inguinal region white with black mottling; posterior surfaces of thighs yellowish tan proximally, dark brown distally; margins of lips grayish white with brown markings; ventral surfaces of hands and feet grayish brown; belly and posterior part of throat creamy white; anterior part of throat brown.

_Description and variation._--Ten breeding males from Finca La Sumbadora, Panama, have snout-vent lengths of 40.0 to 44.8 mm. (42.3 mm.). In these specimens the tibia/snout-vent length ratio is 0.50 to 0.57 (0.54), and the tympanum/eye ratio is 0.48 to 0.58 (0.53). There is a geographic gradient in size; specimens from the western part of the range (southern Costa Rica) are smaller than those from the eastern part of the range (eastern Panama). Five males from the Pacific lowlands of southern Costa Rica have snout-vent lengths of 31.6 to 38.2 mm. (34.7 mm.); ten males from El Volcan, Chiriqui, Panama, 32.6 to 37.9 mm. (36.4 mm.), and eight males from Barro Colorado Island, Canal Zone, 38.2 to 42.0 mm. (35.6 mm.). These are smaller than the males from Finca La Sumbadora, which is east of the Canal Zone. Ten females from El Volcan have snout-vent lengths of 44.2 to 55.6 mm. (49.2 mm.), as compared 56.1 to 62.2 mm. (58.2 mm.) in three females from Finca La Sumbadora.

Large females have scattered small tubercles on the head and back; tubercles occur in males from Costa Rica and in some males from western Panama. The truncate snout is characteristic of both sexes.

The coloration of _Smilisca sila_ consists of a gray, tan, or pale reddish brown dorsal ground color and a creamy white venter. The dorsum is marked by dark brown, olive-brown, or dark reddish brown spots or blotches (Pl. 7B). Usually the blotches are discrete, but in some individuals they are interconnected and form an irregular dark mark on the dorsum. There is no tendency for the blotches to form transverse bars as in _Smilisca sordida_. In one specimen (KU 80467) the blotches are fused and form two wide irregular longitudinal stripes, as in _Smilisca puma_. In some females the dorsal markings are reduced to a few small spots or are nearly absent (KU 92332), whereas in other females the dorsal markings are bold. In one female (KU 91894) the dorsal markings are narrowly bordered by pale blue, and numerous pale blue flecks are present on the pale brown dorsum. In many individuals of both sexes small white flecks are present on the dorsal surfaces.

Usually the flanks and posterior surfaces of the thighs have black mottling enclosing pale blue spots and flecks, respectively. The dorsal surfaces of the limbs are marked by dark brown transverse bars; usually three or four bars are present on each forearm, thigh, and shank. The coloration of the flanks and limbs varies geographically. Specimens from southern Costa Rica and western Panama have distinct bars on the limbs; the posterior surfaces of the thighs have brown reticulations enclosing small blue flecks in specimens from Costa Rica and bolder, black reticulations enclosing large pale blue spots in specimens from western Panama. In specimens from Costa Rica the flanks are brown with pale blue flecks, whereas in those from Chiriqui, Panama, the flanks are pale blue with dark brown mottling in the inguinal region. Frogs from El Valle and Cerro la Campana usually have distinct bars on the limbs; the posterior surfaces of the thighs are colored as in frogs from Chiriqui, and the inguinal region is pale blue with coarse brown mottling. Specimens from Barro Colorado Island are marked like those from El Valle and Cerro la Campana, except that on the posterior surfaces of the thighs fine black reticulations enclose many dark blue spots. In specimens from Darien and from Panama Province east of the Canal Zone (Altos de Pacora, Cerro Jefe, Finca La Sumbadora, and Rio Pacora), the markings on the dorsal surfaces of the limbs are indistinct or absent in males, but distinct in some females. Intense brown and black pigment forms fine reticulations delimiting bold blue spots on the flanks; this coloration extends to the axilla in many specimens. Fine black reticulations enclose many dark blue spots on the posterior surfaces of the thighs.

In females, the throat is creamy white; in some specimens scattered brown flecks are present on the chin and throat. In breeding males the anterior part of the throat is dark gray or dark brown.

The coloration in life is as variable as it is in preservative. In life the holotype had a tan dorsum with dark olive-green irregular markings and small green flecks. The limbs were tan with dark brown transverse bars. The flanks were grayish tan anteriorly; the inguinal region and posterior surfaces of thighs were blue with black mottling. The belly was creamy white, and the throat was brown with creamy yellow flecks. The iris was a dull bronze color. Among the paratypes, some individuals had green flecks, others did not. The inguinal region and posterior surfaces of the thighs were pale blue, pale yellowish green, or grayish tan with black mottling. The blue was most noticeable in females.

Colors of a male from Finca La Sumbadora, Panama, were described as follows: "Dorsum olive-brown; irregular dark brown blotches, pale green flecks, and raised creamy yellow spots on dorsal surfaces; belly creamy white; throat grayish brown; undersides of limbs grayish tan; groin, anterior and posterior surface of thigh, inner surface of shank, anterior edge of tarsus, and proximal parts of third and fourth toes pale blue marbled with dark brown and black; webbing brown; iris pale bronze, finely reticulated with black." (Duellman, field notes, January 28, 1964.)

A female (now KU 91894) from Altos de Pacora, Panama, was described as follows: "An irregular dark brown, green-bordered figure on head and back; dark brown, green-bordered bands on limbs--all on a lighter brown and heavily green-spotted background. These markings are more vivid at night than during the day. Lower sides, from midbody onto front of thighs and rear of thighs onto venter of shanks to heels and thence dorsally onto basal portions of toes heavily blue spotted on a light brown (front of thighs and venter of shanks) to blackish brown background. Venter cream. Iris gray-brown, finely veined with dark brown." (Charles W. Myers, field notes, December 14, 1964.) Note that in the earlier discussion of coloration of preserved specimens, the green spots and borders have changed to pale blue after six months in alcohol.

In living individuals from Costa Rica and Panama west of the Canal Zone, the blue coloration on the flanks and thighs is much less conspicuous than in specimens from eastern Panama. The color of the iris is variable, even in frogs from one locality. The coloration of the iris in 13 living frogs (now KU 92333-45) from Valle Hornito, Chiriqui, Panama, was described as follows: "Iris variable--from pale to dark brown; in a few the iris has a golden cast to the brown; in a few others the lower half of the iris is pale gray with the upper half being light brown." (Charles W. Myers, field notes, April 24, 1965).

_Natural history._--_Smilisca sila_ inhabits the Pacific slopes of lower Central America where a pronounced dry season occurs. We have records of males calling in December through May and also in August (latter date from El Volcan, Chiriqui, Panama). The breeding season seems to be correlated with the time of the year when the water is clear and at a low level in the streams where these frogs breed.

Males call from the edges of small, shallow streams, from rocks in the streams, or less frequently from vegetation overhanging the streams. Females are most frequently found on the banks of streams, and clasping pairs usually are in shallow pools in streams. One individual was found in a bromeliad about three meters above the ground in the daytime.

The breeding call consists of a low squawk, usually followed by a series of one or more rattling secondary notes (duration of primary notes, 0.06 to 0.28 seconds; of secondary notes, 0.14 to 0.48 seconds), repeated at intervals of 4 to 20 seconds. The primary notes have 97 to 120 pulses per second and major frequencies of about 900 to 2220 cycles per second (Pl. 11B).

Eggs were obtained artificially in the field; the average length of ten embryos in the neural groove stage is 2.4 mm., and the average diameter of the outer envelope is 4.9 mm. Hatchlings have large, conical oral discs, heavy gills, and a large amount of yolk; their average total length is 6.3 mm.

Tadpoles have been found in pools in clear streams; some tadpoles have been observed to cling by their mouths to rocks in the stream; others were found on the bottom where they seek refuge among pebbles or under rocks and leaves. A complete developmental series of tadpoles is not available. Eleven tadpoles in stage 25 of development have body lengths of 8.3 to 10.2 mm. (9.3 mm.), tail lengths of 17.3 to 21.0 mm. (18.8 mm.), and total lengths of 25.9 to 31.0 mm. (28.1 mm.). One tadpole in stage 41 and one in stage 42 have body lengths of 11.5 and 12.5 mm., tail lengths of 27.2 and 29.5 mm., and total lengths of 38.7 and 42.0 mm., respectively. The snout-vent lengths of two specimens in stage 43 and one in stage 45 are 12.7, 13.0, and 13.6 mm., respectively.

A typical tadpole in stage 25 of development (KU 80620 from Finca La Sumbadora, Panama) has a body length of 9.5 mm., tail length of 19.0 mm., and a total length of 28.5 mm.; body only slightly wider than deep, nearly flat dorsally; snout broadly rounded in dorsal view, bluntly rounded in lateral view; eyes widely separated, directed dorsolaterally; nostril slightly closer to eye than to tip of snout; mouth ventral; spiracle sinistral, located about two-thirds distance from snout to posterior edge of body; anal tube dextral; caudal musculature moderately heavy, straight; dorsal fin not extending onto body; fins deepest at about two-fifths length of tail, where depth of caudal musculature about equal to depth of dorsal and depth of ventral fin; musculature extending nearly to tip of tail; body dark grayish brown above and pale grayish tan below with small dark brown spots dorsally and white flecks laterally; caudal musculature pale tan with dark brown flecks over entire surface and dark brown streaks on posterior one-half of ventral fin and on all of dorsal fin (Fig. 14B). Median one-third of upper lip bare; rest of mouth bordered by a single row of conical papillae; lateral fold present; tooth rows 2/3; upper rows cone-shaped, about equal in length, broadly /\-shaped; second upper row narrowly interrupted medially; lower rows complete, about equal in length, but slightly shorter than upper rows; upper beak moderately massive, its inner surface forming a continuous arch with short lateral processes; lower beak broadly \/-shaped; both beaks finely serrate (Fig. 15D).

Tadpoles from El Volcan, Chiriqui (KU 91833), are more heavily pigmented than those from Finca La Sombadora; the spots on the tail are larger. In life these tadpoles had dark brownish black bodies with golden and green lichenous flecks; the tail was tan with dark brown markings, and the iris was a grayish bronze color. In life tadpoles from Finca La Sumbadora were olive-tan above and dark gray with pale bluish gray irridescent spots ventrally. The caudal musculature was creamy tan with brown flecks and streaks, and the iris was pale bronze.

Metamorphosing young have been found on vegetation at the edge of streams and have been raised in the laboratory. Seven recently metamorphosed young have snout-vent lengths of 13.6 to 15.6 mm. (14.6 mm.). A living juvenile (KU 91913) raised in the laboratory from a tadpole obtained at Finca La Sumbadora had a brown dorsum with darker brown markings, a white spot below the eye, and a narrow white labial stripe. The belly was white; the flanks were brown with white spots, and the posterior surfaces of the thighs were yellowish tan. The iris was a golden bronze color with much black reticulation.

_Remarks._--This species has been confused with _Smilisca sordida_; most authors have referred both species to _Hyla (Smilisca) gabbi_. Examination of the types of _Hyla sordida_, _gabbi_, _salvini_, and _nigripes_ revealed that all of the names were referable to a single species (_S. sordida_), and that the small, blunt-snouted species in Panama and southern Costa Rica probably was without a name. Possibly _Hyla molitor_ Schmidt (1857) is based on the species that we have named _S. sila_, but several discrepancies in his description, plus the unknown provenance of the type, have led us to discount the applicability of that name to the species under consideration.

_Distribution._--_Smilisca sila_ ranges along the Pacific slopes and lowlands of southern Costa Rica and Panama at elevations from sea level to about 1300 meters; in northern South America the species occurs in the Caribbean lowlands and in the valleys of the northward draining rivers of Colombia (Fig. 3).

_Specimens examined_, 234, as follows: COSTA RICA: =Puntarenas=: 6 km. E Golfito, KU 91717; Quebrada Boruca, 22 km. E Palmar Norte, KU 64265-6; Rio Zapote, 7 km. E Palmar Norte, USC 7100 (2). =San Jose=: San Isidro el General, KU 28200; 14 km. NW San Isidro el General, USC 7098 (2); 15 km. WSW San Isidro el General, USC 7097.

PANAMA: =Canal Zone=: Barro Colorado Island, AMNH 62320-3, CNHM 13324, 13326-8, 13330, 13338, 13359, 13423-5, KU 80460-6, 80619 (young), 80625 (skeleton), UMMZ 63542-6, USC 7051. =Chiriqui=: Boquete, AMNH 69815, UMMZ 58441-5; El Volcan, KU 77413, 91828-31 (skeletons), 91852-74, 91832 (eggs), 91833 (tadpoles); 6 km. S El Volcan, CNHM 60442; 16 km. NNW El Volcan, KU 91879-90; Finca Palosanto, 6 km. WNW El Volcan, KU 77406-12, 77692 (skeleton), 91875-7, 92330-1; Rio Colorado, 17 km. NNW El Volcan, KU 91878, 92332; Valle Hornito, 19 km. NE Gualaca, KU 92333-45. =Cocle=: El Valle, AMNH 55440-5 (13), 59607-14, CNHM 48140, 60349-2, 60387-92, 60401-4, 60443, 67842-5, KU 91834 (young), 91902-4, TNHC 23751-2, USNM 140653. =Colon=: Rio Candelaria, AMNH 53708-15, CNHM 67826-36. =Darien=: Camp Creek, Camp Townsend, AMNH 40756-7, 40936-9, 40992; Rio Chico, AMNH 39784, 40986-7; Rio Pita, CNHM 67823-5; Tacarcuna, USNM 141796-802; Three Falls Creek, AMNH 41684, 51788. =Los Santos=: Cerro Hoya, USNM 148213-4; Lajamina, Rio Puria, KU 67915. =Panama=: Altos de Pacora, KU 91894; Cerro Jefe, KU 91895-6; Cerro La Campana, CNHM 67846, KU 91897-900, USNM 139689; Finca La Sumbadora, KU 80467-81, 80620 (tadpoles), 91910 (eggs), 91911-2 (tadpoles), 91913 (young), 91908-9 (skeletons); Rio Calobra, USNM 53722, Rio Pacora, 9 km. NNE Pacora, KU 91901. =Veraguas=: Cerro Carbunco, USNM 129066; Cerro Tute, CNHM 67837-41; Isla Cebaco, Rio Platanal, KU 91891-3.

COLOMBIA: =Antioquia=: Uraba, Villa Arteaga, CNHM 63893 (Goin). =Atlantico=: Sabanalarga, Rio Causa, AMNH 14506.

=Smilisca sordida= (Peters), new combination

_Hyla sordida_ Peters, Monatsb. Konigl. Akad. Wissen. Berlin., p.
460, 1863 [Syntypes.--ZMB 3141 (two specimens) from "Veragua,"
Panama; J. von Warszewicz collector]. Brocchi, Mission scientifique
au Mexique ..., pt. 3, sec. 2, Etudes sur les batrachiens, p. 42,
1881. Boulenger, Catalogue Batrachia Salientia in British Museum,
p. 393, Feb. 1, 1882. Guenther, Biologia Centrali-Americana:
Reptilia and Batrachia, p. 273, Sept. 1901. Nieden, Das Tierreich,
Amphibia, Anura, I, p. 258, June, 1923.

_Hyla gabbi_ Cope, Jour. Acad. Nat. Sci. Philadelphia, new ser., 8,
pt. 2:103, 1876 [Syntypes.--USNM 30658-9 from near Sipurio, Limon,
Costa Rica; William M. Gabb collector]. Brocchi, Mission
scientifique au Mexique ..., pt. 3, sec. 2, Etudes sur les
batrachiens, p. 37, 1881. Boulenger, Catalogue Batrachia Salientia
in British Museum, p. 372, Feb. 1, 1882. Cope, Bull. U. S. Natl.
Mus., 32:32, 1887. Guenther, Biologia Centrali-Americana: Reptilia
and Batrachia, p. 274, Sept. 1901. Werner, Abhand. Konigl. Akad.
Wissen. Muenchen., 22:351, 1903. Nieden, Das Tierreich, Amphibia,
Anura I, p. 252, June, 1923. Taylor, Univ. Kansas Sci. Bull.,
35(1):840, July 1, 1952. Cochran, Bull. U. S. Natl. Mus., 220:54,
1961.

_Hyla nigripes_ Cope, Jour. Acad. Nat. Sci. Philadelphia, new ser.,
8, pt. 2:104, 1876 [Syntypes.--USNM 30685-6, from Pico Blanco,
Costa Rica; William M. Gabb collector]. Brocchi, Mission
scientifique au Mexique ..., pt. 3, sec. 2, Etudes sur les
Batrachiens, p. 38, 1881. Boulenger, Catalogue Batrachia Salientia
in British Museum, p. 394, Feb. 1, 1882. Cope, Bull. U. S. Natl.
Mus., 32:32, 1887. Guenther, Biologia Centrali-Americana: Reptilia
and Batrachia, p. 278, Sept., 1901. Nieden, Das Tierreich,
Amphibia, Anura I, p. 253, June, 1923. James, Copeia, 3:147, Sept.
30, 1944. Taylor, Univ. Kansas Sci. Bull, 35(1):853, July 1, 1952.
Cochran, Bull. U. S. Natl. Mus., 220:56, 1961.

_Hyla salvini_ Boulenger, Catalogue Batrachia Salientia in British
Museum, p. 372, Feb. 1, 1882 [Syntypes.--BMNH 1947.2.24.13-14 from
Cartago, Costa Rica; Osbert Salvin collector]. Guenther, Biologia
Centrali-Americana: Reptilia and Batrachia, pl. 71, Fig. B., Sept.,
1901. Werner, Abhand. Zool.-Bot. Gesell. Wien, 46:8, Sept. 30,
1896.

_Smilisca gabbi_, Starrett, Copeia, 4:303, Dec. 30, 1960.

_Diagnosis._--Size moderate ([M] 45 mm., [F] 64 mm.); skull slightly wider than long, having large and elongate frontoparietal fontanelle; supraorbital flanges absent; squamosal small, not contacting maxillary; bony section of ethmoid terminating just anterior to anterior edge of orbit; tarsal fold weak, full length of tarsus; inner metatarsal tubercle long, low, flat, elliptical; lips thin and flaring; fingers one-half webbed; toes four-fifths webbed; diameter of tympanum about one-half that of eye; no white labial stripe; dorsal dark markings irregular, sometimes forming broad transverse bars; pale flecks on flanks and usually on posterior surfaces of thighs; vocal sacs in breeding males white. (Foregoing combination of characters distinguishing _S. sordida_ from any other species in genus.)

_Description and variation._--Ten breeding males from 15 to 20 kilometers west-southwest of San Isidro el General, San Jose, Costa Rica, have snout-vent lengths of 38.1 to 42.6 mm. (40.5 mm.). In these specimens, the tibia/snout-vent length ratio is 0.50 to 0.54 (0.52), and the tympanum/eye ratio is 0.45 to 0.57 (0.49). Specimens from the Pacific slopes of Costa Rica are larger than those from the Meseta Central and the Caribbean lowlands. Ten males from 6 kilometers east of Golfito, Puntarenas, have snout-vent lengths of 38.4 to 44.6 mm. (41.8 mm.), and five males from Rincon, Peninsula de Osa, have snout-vent lengths of 38.8 to 41.6 mm. (40.3 mm.). Snout-vent lengths of ten males from La Fortuna, Alajuela, are 31.9 to 36.0 mm. (34.4 mm.), of ten males from Pandora, Limon, 33.8 to 37.6 mm. (35.9 mm.), and of ten males from Escazu and Rio Jorco on the Meseta Central, 34.3 to 37.6 mm. (36.0 mm.). Eight females from the Rio Jorco on the Meseta Central have snout-vent lengths of 48.8 to 53.8 mm. (50.4 mm.), and six females from various localities on the Pacific slopes of Costa Rica have snout-vent lengths of 56.5 to 64.0 mm. (59.8 mm.). The only noticeable differences in proportions between males and females is in the tympanum/eye ratio; for example, this ratio is 0.47 to 0.53 (0.49) and 0.54 to 0.68 (0.61) in ten males and eight females, respectively, from the Meseta Central.

The shape of the snout and the associated cranial elements of _S. sordida_ vary geographically and ontogenetically. Specimens from the Caribbean lowlands have blunt snouts in lateral view; those from the Pacific lowlands have longer, more slender snouts that are pointed in lateral view, and those from the Meseta Central are intermediate in snout shape between the two lowland populations (Fig. 4). These differences in shape of the snout are dependent on the nature of the underlying cranial bones, principally the maxillaries and nasals. In specimens from the Caribbean lowlands the nasals are long, wide, and narrowly separated from the ethmoid; the anterior edge is just posterior to the nostril. The maxillary flanges are nearly vertical. In specimens from the Pacific lowlands the nasals are relatively shorter, narrower, and rather widely separated from the ethmoid; the anterior edges of the nasals do not extend so far forward as in specimens from the Caribbean lowlands. The maxillary flanges slant medially. In these cranial characters, specimens from the Meseta Central are intermediate between the two lowland populations.

Superimposed on this geographic variation are ontogenetic changes, which are most noticeable in males. In smaller, and presumably younger, specimens the snouts are more pointed than in larger specimens; consequently some small males from the Caribbean lowlands resemble larger males from the Pacific lowlands, since the nasals and maxillaries of the former are not fully ossified. In addition, in small breeding males the ethmoid is only about one-half ossified, a large frontoparietal foramen is present, the anterior arm of the squamosal extends only about one-fourth the distance to the maxillary (two-thirds the distance in larger specimens), and the tegmen tympani are short, as compared with the long, thin elements in larger specimens.

The dorsal ground-color of _Smilisca sordida_ is gray to pale tan or reddish brown; the venter is white. The dorsum is variously marked with dark gray, dark brown, reddish brown, or olive-green spots or blotches (Pl. 7C). A dark interorbital bar usually is present. The dorsal markings on the body usually consist of a blotch, or two or more spots, on the occiput, in the scapular region, and in the sacral region. In many specimens, especially females, these markings are in the form of broad transverse bars. A female (USC 7164) from Las Canas, Guanacaste, Costa Rica, has a tan dorsum with many black flecks and round brown spots bordered by darker brown. One female (KU 91763) from the Rio Jorco, San Jose, Costa Rica, has a unicolor tan dorsum. Some individuals have scattered, small white spots on the dorsum; these are most evident in a male (USC 7153) from La Fortuna, Alajuela. White labial stripes and anal stripes are absent in all specimens.

The limbs are marked by dark brown transverse bars; these are indistinct in some specimens from the Meseta Central and Caribbean lowlands, whereas they are distinct in all specimens from the Pacific lowlands. Specimens from the Caribbean lowlands have two to six bars on each shank, whereas specimens from the Pacific slopes have four to six bars on each shank, and specimens from the Meseta Central have as many as eight bars on each shank. A narrow, sometimes broken white line is present on the ventrolateral edge of the forearm. The webbing on the hand is tan or pale gray, and the ventral surfaces of the tarsi and the webbing on the feet are dark gray or brown. Breeding males have dark brown nuptial excrescences on the prepollex.

The flanks and posterior surfaces of the thighs usually are marked by bluish white and creamy tan flecks, respectively, but vary considerably. In specimens from the Caribbean lowlands a small amount of flecking is present in the inguinal region, and on the posterior surfaces of the thighs flecks are few or absent. In specimens from the Meseta Central, numerous large flecks or small, round spots (pale bluish white in life) are on the posterior half of the flanks; small flecks are on the posterior surfaces of the thighs. Specimens from the Pacific slopes and lowlands of southern Costa Rica (Puntarenas and San Jose Provinces) have bold mottling of black and bluish white on the flanks and many bluish white flecks on the posterior surfaces of the thighs. The flanks are reticulated from the axilla to the groin in two females (UMMZ 123684 and USC 7236) from Rincon, Peninsula de Osa. In specimens from the Pacific slopes of Guanacaste in northwestern Costa Rica, flecks are present in the inguinal region; indistinct flecks are on the posterior surfaces of the thighs.

The throat is immaculate in specimens from the Caribbean lowlands in Limon Province; the throats are dusky laterally in most other specimens except some from the Meseta Central, in which the throats are heavily flecked with black. This variation occurs in males and females.

The color and pattern in life are highly variable. A composite description of living individuals (now KU 91718-41) from 6 kilometers east of Golfito, Puntarenas, Costa Rica, illustrates the variability: "Dorsum pale olive-green, fading to tan posteriorly, or tan all over with dark olive-green or dark brown spots on back and bars on limbs. Flanks dark brown with cream, greenish gray, or bluish gray mottling. Posterior surfaces of thighs dark brown with pale blue, pale green, or tan flecks. Iris creamy silver. Throats white with some brown flecks peripherally." (Duellman, Field notes, February 15, 1965.) A male from the Rio Jorco, San Jose, Costa Rica, was dull olive-tan above with olive-green marks; the flanks were brown with pale tan flecks, and the posterior surfaces of the thighs were pale brown with cream-colored flecks. Six females from the same locality were reddish brown above with olive-brown or dark brown markings; one was uniform orange-tan, and another was dull olive-green with darker markings.

The color of the iris in living frogs varies from creamy silver to grayish yellow or bronze with a variable amount of black reticulation.

_Natural History._--_Smilisca sordida_ is not associated with any one type of vegetation; instead it lives in the vicinity of rocky streams having low gradients. Breeding takes place primarily in the dry season, when the water in the streams is clear and at a low level. Through most of the range of _S. sordida_ showers, or even short heavy rains, occur in the dry season. After such rains the breeding activity is maximal. Breeding congregations have been found from December through April, but a few calling males and gravid females have been taken in June, July, and August. In the rainy season non-breeding individuals are found sitting on bushes near streams at night. Taylor (1952:843) found specimens in bromeliads by day.

Males usually call from rocks or gravel bars in, or at the edge of, streams. Some individuals perch in low bushes overhanging the streams, and some sit in shallows in the streams. Clasping pairs have been found on the banks of streams and in shallow water in streams.

The breeding call consists of one to six moderately short, rather high-pitched notes (duration 0.18 to 0.45 seconds) repeated at intervals of 12 seconds to several minutes. Each note is a vibrant rattle having 78 to 135 pulses per second and major frequences of about 1200 to 2600 cycles per second (Pl. 11C).

The tadpoles live in shallow parts of the streams, where they cling to the surfaces of small rocks and hide beneath leaves and rocks. A complete developmental series of tadpoles is not available; measurements of those stages examined are summarized in Table 12.

A typical tadpole in stage 36 of development (KU 68475 from 15 km. WSW of San Isidro el General, Costa Rica) has a body length of 11.7 mm., tail length of 22.8 mm., and a total length of 34.5 mm.; body about three-fourths as deep as wide; snout broadly rounded in dorsal view, sloping and rounded in lateral view; eyes widely separated, directed dorsolaterally; nostril slightly closer to eye than to tip of snout; mouth ventral; spiracle sinistral, about two-thirds distance from snout to posterior end of body and slightly below midline; anal tube dextral; caudal musculature heavy, straight; dorsal fin not extending onto body; fins deepest at about mid-length of tail; there depth of caudal musculature equal to depth of dorsal fin and half again as deep as ventral fin; musculature extending nearly to tip of tail; body reddish brown above and pale grayish brown with white flecks below; caudal musculature pale tan with brown flecks; a series of reddish brown dashes at base of caudal fin separated from others in series and from dashes on other side by creamy white; fins transparent with reddish brown flecks on posterior one-half of ventral fin and on all of dorsal fin (Fig. 14C). Mouth bordered by two rows of short, pointed papillae; lateral fold present; tooth-rows 2/3; upper rows equal in length; second upper row narrowly interrupted medially; three lower rows complete, nearly as long as upper rows, deeply indented medially; upper beak robust, inner surface not forming continuous arch with short lateral processes; lower beak deep, V-shaped; both beaks bearing short serrations (Fig. 15F).

Little variation occurs in structure. In some specimens the second upper tooth-row is complete; no individuals were found to have the row broadly interrupted medially.

The series of dark dashes on the dorsal edge of the caudal musculature is diagnostic of all stages studied. In life, tadpoles from 15 and 20 kilometers west-southwest of San Isidro el General, Costa Rica, had a tan body, often with an olive-tan tinge; the caudal musculature was tan; the flecks and dashes were dull red or reddish brown. Tadpoles from 6 kilometers east of Golfito, Costa Rica, had bodies with olive-green flecks. The caudal musculature was brown with bluish green flecks; the fins were transparent with reddish brown flecks. The belly was a silvery golden color. Tadpoles from Bajos de Jorco, Costa Rica, had brown bodies with bluish green flecks; the tail and fins had reddish brown flecks and dashes. The iris was a bronze color in specimens from all three localities, as well as in the young mentioned in the following paragraph.

Nine recently metamorphosed young were found on vegetation at the edges of streams in April. These specimens have snout-vent lengths of 13.1 to 15.7 mm. (14.9 mm.) and in life were pale greenish tan or olive-tan above and white below. The hands, feet, and thighs were pale yellowish tan.

_Remarks._--The foregoing synonymies indicate that confusion has existed in the application of various names, to this species, as well as in use of the names _sordida_ and _gabbi_ to include the species that we describe and name _Smilisca sila_. Correct allocation of the names involved was possible only after studying and comparing the type specimens, for the descriptions given by the various authors are not sufficiently explicit to determine the nature of many essential features.

The presence of a rounded snout and a long white throat in males distinguishes _S. sordida_ from _S. sila_, which has a high truncate snout and short dark throat in males. The two syntypes of _Hyla sordida_ Peters, 1863, (ZMB 3141) are males having snout-vent lengths of 36.9 and 37.0 mm. The two syntypes of _Hyla gabbi_ Cope, 1876 (USNM 30658-9), are females having snout-vent lengths of 52.8 and 53.7 mm., respectively. Also included in the collections made by Gabb is eastern Costa Rica are two males (USNM 30685-6), which Cope (1876) named and described as _Hyla nigripes_. These specimens are soft and faded, but are recognizable as the same as _Hyla sordida_ Peters; the syntypes of _Hyla nigripes_ have snout-vent lengths of 37.6 and 37.7 mm. We have examined one of the syntypes of _Hyla salvini_ Boulenger, 1882 (BMNH 1947.2.24.13), a female having a snout-vent length of 54.6 mm. We are convinced that all of these type specimens are representatives of one species, the earliest name for which is _Hyla sordida_ Peters, 1863. The type localities for three of the named species are in Costa Rica--_H. gabbi_ from Sipurio on the Caribbean lowlands, _H. nigripes_ from the Caribbean slopes of Pico Blanco, and _H. salvini_ from Cartago on the Meseta Central. The type locality of _H. sordida_ was given as "Veraguas" by Peters (1863). At that time Veraguas was often considered to be most of western Panama. Though we have not seen Panamanian specimens other than the types of _S. sordida_ and one specimen from the Pacific lowlands of western Panama, the species probably occurs on the Caribbean slopes of western Panama. The species has been taken on the Caribbean lowlands of Costa Rica within a few kilometers of Panama; collecting on the Caribbean slopes in the provinces of Bocas del Toro and Veraguas should reveal the presence of _Smilisca sordida_ there.

_Distribution._--_Smilisca sordida_ is found along the Pacific slopes and lowlands from Guanacaste, Costa Rica, southeastward to extreme western Panama, to elevations of about 1200 meters on the Meseta Central in Costa Rica, and on the Caribbean slopes and lowlands of Costa Rica and probably adjacent Panama (Fig. 5). One specimen purportedly comes from "Rio Grande, Nicaragua."

_Specimens examined._--412, as follows: NICARAGUA: "Rio Grande" (? Depto. Zelaya), MCZ 2634.

COSTA RICA: =Alajuela=: Between Atena and Salto de San Mateo, USC 6185; 8 km. N Ciudad Quesada, USC 7155 (4); La Fortuna, USC 7153 (20); 3 km. E La Fortuna, USC 7150; San Carlos, USNM 29969; Sarchi, KU 32990-9, 36792-3.

=Cartago=: Cartago, BMNH 1947.2.24.13; headwaters of Rio Pacuare, USC 119; Instituto Interamericano de Ciencias Agricolas, Turrialba, KU 37012, USC 420, 437; Rio Reventazon, Turrialba, MCZ 29268: 10 km. N Rio Reventazon bridge, USC 7073; 5 km. SW Rio Reventazon bridge on Paraiso-Orosi road, USC 669; Turrialba, UMMZ 118405, USC 455, USNM 29936-9.

=Heredia=: Puerto Viejo, KU 36791.

=Guanacaste=: Las Canas, USC 7164; Santa Cecilia, MCZ 7924-5; Tilaran, USC 7161 (5).

=Limon=: Bambu, USC 7171 (2), 7183 (13); La Lola, USC 820 (6), 6083-94, 8064, 8071; Pandora, USC 7188 (7), 7189, 7190 (3), 7191 (5); Pico Blanco, USNM 30685-6; Rio Lari, 14-16 km. SW Amubre, USC 7179, 7180 (10); Sipurio, USNM 30658-9; Suretka, KU 36764, 36765 (skeleton), 36766-78.

=Puntarenas=: 6 km. N Dominical, KU 91749-50, 91811 (young), 91812 (tadpoles); Esparta, MCZ 8028; 6 km. E Golfito, KU 91718-41, 91809 (young), 91810 (tadpoles), 91816-9 (skeletons), USC 7103 (23); Quebrada Agua Buena, 3 km. SW Rincon de Osa, USC 7236 (6); Quebrada Boruca, 22 km. E Palmar Norte, KU 64264; Rincon de Osa, Camp Seattle, UMMZ 123680-5, S-2792 (skeleton), USC 705 (5), 6023, 7254; Rio Barranca, USC 7119 (2); Rio Ceiba, 6 km. NW Buenos Aires, KU 91747-8, USC 7112 (7); Rio Ciruelitas, 16 km. NW Esparta, USC 7121 (3); Rio Claro, 14.2 km. NW Villa Neily, USC 7110 (4); Rio Ferruviosa, 7 km. S Rincon de Osa, USC 7235 (4); Rio Lagarto at Pan-American Hwy. (Guanacaste Border), USC 7122 (4); Rio La Vieja, 30 km. E Palmar Norte, KU 87684 (tadpoles), 91743-6, USC 7083 (2); Rio Oro, 28.5 km. NW Villa Neily, KU 91742; Rio Volcan, 10 km. W Buenos Aires, USC 7113; Rio Zapote, 7 km. E Palmar, USC 7100 (4); 3-5 km. W Palmar, USC 7101 (18); 7 km. SE Palmar, KU 64261-3; 1.2 km. NW Villa Neily, USC 8032; 3 km. NW Villa Neily, USC 7109 (20); 5 km. NW Villa Neily, USC 6176, 8035.

=San Jose=: Bajos de Jorco, KU 91813 (tadpoles); Escazu, KU 34863, 34869-75, USC 813; between Monrovia and La Hondura, +- 0.5 km. N Santa Rosa, USC 302 (2); Paso Ancho, Rio Jorco, UMMZ 122649 (6), USC 530 (3); Rio Jorco, near Desamparados, KU 91757-65, 91796-7, 91820-3 (skeletons), USC 228, 513, 7117 (7); Rio Peje, 10 km. SSE San Isidro el General, USC 7115 (3); Rio Tirivi, MCZ 7972; San Isidro el General, CNHM 101096, KU 28201, 32989, UMMZ 72024; 15 km. WSW San Isidro el General, KU 64245-56, 68473 (tadpoles), 68474 (young), 68475 (tadpoles), 86516, 91754-6, 91793-5, USC 7097 (6); 17.1 km. WSW San Isidro el General, USC 6047; 18 km. WSW San Isidro el General, USC 689; 20 km. WSW San Isidro el General, KU 64257-9, 64260 (skeleton), 68468 (young), 68469 (tadpoles), 68470 (young), 68471-2 (tadpoles), 68476 (young), 68633-4 (skeletons), 91751-3; San Jose, AMNH 7501-4, USC 298; Santa Rosa, Rio Virilla, USC 7145.

PANAMA: =Chiriqui=: Rio Jacu, 5.8 km. ESE Paso Canoas, KU 91905. "Veraguas," ZMB 3141 (2).

ANALYSIS OF MORPHOLOGICAL CHARACTERS

Osteology

In attempting to assay the taxonomic significance of skeletal differences we are faced with a dearth of data on the skeletons of frogs in general and hylids in particular. Recent reviews by Brattstrom (1957) and Hecht (1962, 1963) have been concerned with general salientian classification and phylogeny, principally at the family level. Savage and Carvalho (1953), Griffiths (1959), and Baldauf (1959) used osteological characters in determining the taxonomic status of the families Pseudidae, Brachycephalidae, and Bufonidae, respectively. Carvalho (1954) presented osteological evidence for the generic separation of New World microhylids. Zweifel (1956) and Tihen (1962) used osteological characters at the levels of the species-group and species in their respective studies on _Scaphiopus_ and _Bufo_. Little has been recorded about the skeletons of the hylids. Goin (1961) mentioned dentigerous elements and cranial co-ossification in his synopsis of the genera of hylids. Copland (1957) in his review of the _Hyla_ of Australia, Funkhouser (1957) in her revision of _Phyllomedusa_, and Zweifel (1958) in his review of _Nyctimystes_ did not consider skeletal characters.

Some osteological studies on hylids have yielded worthwhile information. Mittleman and List (1953) used osteological characters in defining the genus _Limnaoedus_: Starrett (1960) used cranial characters in combination with jaw musculature in defining the genus _Smilisca_, and Duellman (1964) used cranial characters in delimiting the _Hyla bistincta_ group. Brief descriptions of cranial structure were given for _Phrynohyas_ (Duellman, 1956) and _Ptychohyla_ (Duellman, 1963a); specific and sexual differences in the skulls of _Hyla chaneque_ and _Hyla taeniopus_ were pointed out by Duellman (1965). Stokely and List (1954) described early cranial development in the hylid _Pseudacris triseriata triseriata_.

Because our knowledge of the skeleton in hylids is so incomplete, we are not attempting to place _Smilisca_ in the general scheme of hylid phylogeny on the basis of skeletal characters. Instead, our purposes are to describe the skeleton and its ontogenetic development in one member of the genus (_S. baudini_), and to make comparisons that show taxonomic differences in osteological characters among species of _Smilisca_.

The study of 68 dried skeletons and 25 cleared and stained preparations, including an ontogenetic series of _S. baudini_, has resulted in an understanding of the progressive development of skeletal elements and a knowledge of interspecific and intraspecific variation in these elements. Furthermore, investigations of the osteology have provided correlations between some cranial characters and certain aspects of external morphology.

_Descriptive Osteology of Smilisca baudini_

The following description is based primarily on an adult female (KU 68184):

_Skull._--The skull is large, solid, and broader than long; the greatest width is between the sutures of quadratojugal and maxillary on either side of the skull (Pls. 2-3). The maxillaries bear well-developed dorsal flanges, curve gently, join the moderately convex premaxillaries anteriorly and form a slightly truncate snout. The combined premaxillary width is about one-fourth the width of the skull. The premaxillaries are separated medially, and laterally from the maxillaries by sutures. Each premaxillary bears a dorsomedial alary process, which is anteriorly convex and four times as high as the depth of the lateral wing of premaxillary; each premaxillary also has a ventromedial palatine process that projects dorsally from the lingual edge of the premaxillary. The septomaxillaries are closely associated dorsally with the premaxillaries immediately lateral to the prenasal processes.

The nasals are large, widest anteriorly and narrowing posteriorly, parallel to maxillaries, and not separated from the ethmoid by cartilage. The nasals bear long, delicate maxillary processes extending nearly to the maxillaries. Anteriorly, the nasals are widely separated by the partially ossified internasal septum, which is in contact with the premaxillaries between the prenasal processes; the anterior points of the nasals lie approximately one-half the distance between the anterior ends of the ethmoid and the premaxillaries. The ethmoid is large and completely ossified; the margins are smooth. The trunate anterior edge lies between the nasals and is in contact with the internasal septum. The frontoparietals are large, smooth-margined, and bear large supraorbital flanges curving posterolaterally at the rear of the orbit. A small, oval foramen involves the posterior part of the ethmoid and anterior portion of frontoparietals; continued ossification in older specimens fills in the foramen, thereby resulting in a solidly roofed cranium. The auditory regions are relatively massive and bear narrow tegmen tympani; the distal ends of the tegmen tympani are medial to the lateral edge of the pterygoids in dorsal view. The squamosals are large; the long anterior arm is separated from the maxillary by a suture. The delicate, spindle-shaped columellae lie ventral to the tegmen tympani and squamosals, are spatulate distally, and have a broad basal attachment to the auditory region.

The vomers are moderately large and are in contact anteriorly with the premaxillaries and posteriorly with the ethmoid. Each vomer has two wide serrated flanges laterally. The tooth-bearing parts of the vomers are widely separated and at a slight angle to one another; the vomers terminate medially in two pointed processes on the ethmoid. The palatines are edentate, but bear strong ridges throughout their lengths. They are broadly in contact with the maxillary, are narrow medially, and are attached by pointed processes to the medial part of the ethmoid. The pterygoids are large, attached to the maxillaries immediately anterior and medial to the squamosal-maxillary connection, bear well-developed pedicles, which are broadly attached to the prooetic, and a wide wing is in contact posteriorly with the distal two-thirds of the quadrate.

The angular makes up most of the lower jaw, bears a broad articular surface posteriorly, and has a small coronoid process on the lingual edge; anteriorly the angular is separated from the dentary and mentomecklian by Meckel's cartilage. The dentary lies external to the angular and extends from the mentomecklian to approximately the mid-length of the angular. The mentomecklians are ossified, but separated by cartilage medially.

_Hyoid._--The hyoid plate is curved, thin, and mostly cartilaginous, but calcined posteriorly (Fig. 6). The anterior cornua are slender, cartilaginous, and curve anteromedially from the hyoid plate and thence laterally and posteriorly, to attach to the posterior surface of the prooetics. The lateral cornua are broad, flat, cartilaginous lateral extensions from the bases of the anterior cornua. The posterior cornua are bony, except distally.

_Vertebral Column._--The atlas lacks transverse processes and a neural crest, whereas transverse processes are present on the other seven presacral vertebrae, and knoblike neural crests are present on the second, third, and fourth vertebrae; a faint neural ridge is visible on the fifth vertebra. The transverse processes are directed laterally on the second and sixth vertebrae, ventrolaterally on the third, posterolaterally on the fourth and fifth, and anterolaterally on the seventh and eighth. The processes are slightly expanded on the fourth, and more so on the fifth, vertebra. The sacral diapophyses are expanded and have a border of calcified cartilage laterally. There are two sacral condyles. The slender coccyx has a thin dorsal ridge on the anterior three-fourths of its length.

_Pectoral Girdle._--The omosternum is large, ovoid, and cartilaginous; the sternum is a thin cartilaginous sheet deeply notched posteriorly and is not differentiated into episternal and xiphisternal elements. The coracoids are robust, twice as stout as the clavicles. The epicoracoidal cartilages overlap in the usual arciferal manner, except that they are fused anteriorly between the slender clavicles. The clavicles are strongly arched. The clavicle, coracoid, and scapula on each side form a bony articulation at the glenoid fossa. A bifurcation of the ventral end of the scapula results in a large glenoid foramen. The scapula is flat and expanded dorsally; the suprascapula is broad, flat, and calcified in large adults. In young specimens no distinct ossification of the cleithrum or ossification of endochondral centers are evident.

_Arm and Hand._--The humerus is equally well-developed in both sexes and has a prominent lateral crest. The radius and ulna are completely fused. A bony prepollex is present in both sexes. The metacarpals are about equal in length. The phalangeal formula is 2-2-3-3; the terminal phalanges are claw-shaped.

_Pelvic Girdle._--The ilia are long, slender, and slightly curved. A thin ridge projects laterally from the dorsal edge of the posterior one-half of each ilium. The ilial prominence is large and knoblike when viewed from above. The anterior edge of the ilial prominence is at the level of the anterior edge of the acetabular border. The dorsal acetabular expansion is small. The pubis is slender, and the ischium is elevated and robust.

_Leg and Foot._--The slightly curved femur has a distinct crest proximally on the posterior surface. The nearly straight tibio-fibula is slightly longer than the femur. The tibial and fibial elements are completely fused but have a distinct cleft between them. A small foramen exists at the mid-length of the tibio-fibula. The fibulare (calcaneum) is much more robust than the tibiale (astragalus). The prehallux is large and flat. The metatarsals of the third, fourth, and fifth digits are equal in length; the metatarsal of the second is somewhat shorter, and that of the first is much shorter. The phalangeal formula is 2-2-3-4-3; the terminal phalanges are claw-shaped.

_Developmental Cranial Morphology of Smilisca baudini_

The following description of development of the skull of _Smilisca baudini_ is based on the examination of 12 cleared and stained specimens. In table 3 the cranial bones are listed in the left hand column in the approximate order of their appearance in the young frogs. Across the top of the table selected specimens designated by developmental stage or snout-vent length are listed. It should be noted that although each individual, from left to right, has an increasing number of ossified bones, the correlation with increasing size is imperfect; the precise ages of the individuals are unknown.

The first bones to appear are the septomaxillaries, frontoparietals, part of the exoccipital, and the parasphenoid in developmental stage 40. The frontoparietals are represented by two slender ossifications dorsomedial to the orbits; the septomaxillaries are present as small ossifications anterior to the nasal capsules (Pl. 1A). The parasphenoid is present as a faint median ossification, and the exoccipital shows some ossification.

Table 3.--The Order of Occurrence of Cranial Ossifications in the
Skull of Smilisca baudini. Where Numbers Are Divided by a Slash
Mark, the Left and Right Symbols Correspond to the Left and
Right Sides of the Skull, Respectively.