470 U.S. NATIONAL MUSEUM BULLETIN 2 88 



beside this stripe as well as some parts of the dorsolateral ridge clove 

 brown, with some irregular sepia spots on both sides of the latter; 

 upper limb surfaces drab, with five alternately narrow and wide 

 sepia crossbands on tibia, femur, and foot; upper arm ecru drab, 

 with two or three faint darker bands; posterior femur drab with an 

 irregular clove brown network, and a much broken diagonal light line 

 from its midpoint to behind knee; anterior femur ecru drab with dark 

 spots arranged in a wide irregular longitudinal stripe; venter ecru 

 drab, immaculate except for a dark brown line around lower jaw, 

 ending in a dark patch covering external vocal sacs and a few dark 

 spots below tibia and foot; side of head ecru drab, except a slightly- 

 paler line along rim of upper jaw, with a darker suffusion towards 

 the outer edges. 



Variation in distinctness of dorsal folds is quite wide. Some speci- 

 mens have the backs practically smooth (possibly the result of mode 

 of preservation); others have the outer pair distinct and the two 

 inner pairs scarcely apparent; and still others have all three pairs 

 very well developed. 



Color is also variable. Many specimens have a wide pale middorsal 

 stripe. Those without such a stripe have five rather irregular dark 

 transverse bars between shoulders and anus; often these bars are 

 broken up into several large spots that lose their transverse arrange- 

 ment and become scattered over the posterior half of the back. 



The white stripe along the upper lip and the postfemoral white 

 stripe or row of white dots are characteristic both of Leptodactylus 

 sibilatrix and of its ally L. mystaceus. The frogs of the latter species, 

 however, do not have more than one pair of dorsal folds (which act- 

 ually are dorsolateral in position) and the males lack the black lat- 

 eral throat sacs so obvious in sibilatrix. 



Specimens Examined 

 COLOMBIA 



Amazonas: Leticia, USNM 140289. 



Antioquia: Casabe, USNM 147079; near Turbo, Golfo de Uraba, USNM 

 150491-515; Sons6n, MLS 243, AMNH 22609; Villa Arteaga, CNHM 78141. 



BolIvar: Rio Viejo, lower Rio Magdalena, USNM 145777-9. 



C6rdoba: Tierra Alta, 70 m., CNHM 61806. 



Cundinamarca: Beltran on Rio Magdalena, USNM 145743; Cambao, USNM 

 147080-2; Puerto Salgar, MLS 279; Tocaima, MLS 295. 



Magdalena: Fundaci6n, MCZ 8968-9; Ci6naga, USNM 144159-60. 



Meta: Near Puerto L6pez, upper Rio Meta on the Pacicuar&, USNM 146197-9; 

 Macarena and El Mico, upper Rio Giiejar, USNM 144894; Villavicencio, 

 USNM 144895, 147083-7, 147397-8; Granada on Rio Ariari, south of Villa- 

 vicencio, USNM 151495-503; Menegua, east of Puerto L6pez, upper Rio 

 Meta, USNM 147275; San Juan de Arama, 400 m., Los Micos, CNHM 

 81330-1. 



Norte de Santander: Astillero, USNM 1470SS-9, MLS 216; Rio Catatumbo, 



