60 PROCEEDINGS OF THE NATIONAL MUSEUM vol.74 



tip of snout (3.8-5.0 mm.), average 1.38. Nostril 1.0-1.5 nearer eye 

 (1.8-2.5 mm.) than snout (2.0-3.5 mm.), average 1.35. Mouth (2.0- 

 3.5 mm.) 1.0-1.4 in internasal space (3.0-4.0 mm.), average 1.25. 

 Mouth contained 1.6-2.0 (average 1.83) in interorbital distance 

 (5.0-6.0 mm.). Internasal space contained in interorbital space 

 1.25-1.8, average 1.48. 

 The dimensions of the largest tadpole are : 



Mm. 



Total length 40. 



Body length 15. 



Body depth 6. 



Body width 7.0 



Tail length 25. 



Tail depth 8. 



Musculature of tail 4. 



Spiracle to snout 9. 



HYLA REGILLA Baird and Girard 



Mm. 



Spiracle to vent 7. 



Spiracle to eye 3. 



Eye to snout 5. 



Eye to nostril 2. 5 



Nostril to snout 3. 5 



Mouth 3.0 



Interorbital distance 6. 



Internasal distance 4. 



Plate 4, figure 5 



General appearance. — Tadpole medium (45 mm.), full, and deep 

 bodied. Tail medium or fairly long, tip acute or obtuse. No flagellum. 

 The dorsal crest not exceeding the musculature in depth, extending 

 on to body to the vertical through the posterior edge of the eye. 

 Tail in general quite deep. Spiracle sinistral, more directed back- 

 ward than upward, opening plainly visible as a round or elliptical 

 opening. Spiracle far below lateral axis. Eye on the lateral axis, in 

 dorsal aspect on the lateral outline, therefore just visible from venter. 

 Anus dextral, opening just above the level of the lower edge of the 

 ventral crest. Muciferous crypts not distinct. 



Mouth parts. — Teeth -f. Upper labium fringed with a continuous 

 row of teeth; the papillae extend above and inward beyond the end 

 of upper fringe one-seventh to one-fifth (usualty one-fifth) of the 

 length of the upper fringe. The end of the second upper labial row 

 may extend beyond the end of the upper fringe or be even with it. 

 The horny beak may be contained in horny fringe or combined upper 

 lateral rows 1.8-1.4 times. Median space between these lateral 

 rows contained usually three (sometimes 2.5-5.0 times) times the 

 length of the lateral rows. Usually a well-formed inner row of papillae 

 on side of labium down almost to the end of the lower labial row. 

 The third row of lower labial teeth with only a single row of papillae 

 below it as in H. crucifer or H. gratiosa and unlike the other five or 

 six species studied. Third row usually contained about three times 

 in length of first or second lower labial teeth rows (sometimes 2.5-3). i 

 The first and second lower labial teeth longer than beak. 



Measurements. — Length of body (13.0-16.0 mm.) in tail (20-30 

 mm.) 1.46-1.875, average 1.68. Width of body (6.2-9.4 mm.) in its 

 own length 1.6-2.1, average 1.74. Depth of body (5.0-9.8 mm.) 



