ART. 1! NORTH AMERICAN TADPOLES — WRIGHT / 



hK Median space in second upper labial row 2-4 times the length of either lateral 

 part; third row of lower labial teeth 0.33-0.66 shorter than the first or second 

 rows, usually at least 0.50; eye nearer the snout than spiracle or equidistant; 

 nostril nearer eye than tip of snout; depth of tail in length of tail 2.3-3.2, 

 average 2.7; spiracle 1.5-1.8 nearer eye than snout, average 1.63. 

 Hudson Bay-Louisiana and Eastern States. (PI. 2, fig. 8.)-.Rana palustris. 



/i2. Median space 0.5-1.0 or 1.0-1.5 times either lateral part of the second upper 

 row; third row of labial teeth 0.22 or 0.285-0.33 shorter than the first lower 

 row; depth of tail in length of tail 2.0-2.8 or 2.7-3.4. 



{'. Median space of second upper row 0.5-1.0 times either lateral part; third 

 lower row of teeth 0.285-0.33 shorter than the first lower row; nostril to 

 snout equal to nostril to eye; eye 1.15-1.3 nearer tip of snout than spiracle, 

 average 1.2; body length in tail length 1.35-1.66, average 1.5; mouth 

 0.9-1 .6 larger internasal space; depth of tail in length of tail 2.0-2.88, average 

 2.65; tail crest usually with white prominent dark spots; greatest length of 

 tadpole 74 mm.; spiracle 1.1-1.86 nearer eye than snout, average 1.46. 

 Southeastern States-Louisiana. (PI. 2, fig. 2.) Rana sphenocephala. 



i^. Median space 1.0-1.5 times either lateral part; third lower row 0.22 shorter 

 than the first lower row; nostril 1.1-1.5 nearer the eye than snout; eye nearer 

 spiracle than snout 1.1-1.3; body length in tail length 1.3-2.0, average 1.7; 

 mouth larger than internasal space; depth of tail in length of tail 2.7-3.4, 

 average 3.0; tail crest usually translucent with fine spots or pencilings; 

 greatest length of tadpole 84 mm.; spiracle 1.4-1.86 nearer eye than snout, 

 average 1.59. 

 North America east of Sierra Nevada southward into Mexico. (PI. 2, fig. 5.) 



Rana pipiens. 



p. Tadpoles 84-142 mm.; tadpoles usually winter over at least one season; 

 transformation sizes 28-59 mm. (except R. virgatipes 25-35 mm., possibly 

 R. onca); tadpoles usually with strongly pigmented bellies, viscera not 

 plainly showing through the skin (in spirit specimens) . 



(?'. Tadpole with prominent continuous black crest margins and a black muscula- 

 ture band; belly blusish; tadpoles to 95 mm.; young tadpoles black with 

 transverse yellowish band on the body; spiracle 0.86-1.2 nearer vent or base 

 of hind legs than snout, average 1.0; spiracle 0.85-1.2 nearer eye than base 

 of hind legs or vent, i. e., usually equidistant; eye equidistant from spiracle 

 and tip of snout; muciferous crypts very distinct; spiracle below lateral 

 axis; tail tip acuminate; second upper labial row in upper fringe M to 34; 

 upper fringe distinctly greater than horny beak; median space between 

 two parts of second upper labial row 1 to IH of either lateral part; third 

 lower labial row equal to horny beak; third lower labial row longer than 

 single row of lower papillae; third lower labial row J4 to J^ shorter than 

 first lower row. Eggs unknown. 

 South Carolina-Florida. (PI. 3, figs. 1, 2.) Rana heckscheri. 



g'. Tadpole without black crest margins or lateral band; belly white, cartridge 

 buff, buff or yellow to maize yellows; no transverse yellow band in young 

 tadpoles; spiracle nearer vent than snout 1.1-1.8; spiracle to eye rarely less 

 than 1.25 greater than spiracle to vent; eye near tip of snout than spiracle 

 1-1.4; second upper labial row in upper fringe 34 to Yis] upper fringe equal 

 to or slightly greater than horny beak; median space in either lateral part 

 13^ to 11; third lower labial row much less (about 13^) than horny beak; 

 third lower row much shorter or equal to single row of lower labial papillae. 

 hK Tadpoles to 140 mm.; ej'e well above lateral axis; muciferous crypts indistinct; 

 spiracle just below lateral axis; spiracle 1.08-1.44 nearer base of hind legs 

 or vent than tip of snout, average 1.26; depth of tail in tail length of tail 



