_Tadpoles._--Three hundred and thirty-one tadpoles in various stages of development are available. Thirty-five tadpoles in stage 35 have a mean body length of 8.1 mm. (8.0-9.0 mm.), tail length of 17.7 mm. (15.0-19.5 mm.), and total length of 25.9 mm. (23.0-27.5 mm.). The largest tadpole examined is in stage 40 and has a total length of 34.5 mm. (Table 6). A typical tadpole, stage 35 of development (KU 104134, from Puerto Viejo, Heredia Province, Costa Rica), has a body length of 9.1 mm., tail length of 17.7 mm., and a total length of 26.8 mm. Other characters are as follows: body depressed anteriorly; body length greater than depth of tail; internarial space as broad as interorbital distance; nostril equidistant between eye and tip of snout; eyes moderately large; mouth anteroventral and triangular; median fourth of upper lip bare; rest of lip bordered by one row of papillae; clumps of small papillae at corners of mouth; tooth rows 2/3; upper rows equal in length; second row interrupted medially; lower rows shorter than upper rows, diminishing in length; beak rather weak with small serrations; spiracle short and nearer eyes than anus; anal opening not reaching edge of ventral fin; caudal musculature attenuated distally (Figs. 2B and 3B). TABLE 6.--Sizes of Tadpoles of _Hyla elaeochroa_ in Relation to Developmental Stages. (Means in parentheses below observed ranges; measurements in mm.) ------+---+-------------+-------------+-------------- Stage | N | Body length | Tail length | Total length ------+---+-------------+-------------+-------------- 24 | 2 | 4.0-4.0 | 8.5-9.0 | 12.5-13.0 | | (4.0) | (8.8) | (12.8) | | | | 25 |64 | 5.0-6.5 | 8.5-15.0 | 13.5-21.5 | | (5.7) | (11.8) | (17.6) | | | | 27 |30 | 7.0-7.5 | 13.0-16.0 | 20.0-23.0 | | (7.1) | (14.2) | (21.3) | | | | 30 |15 | 7.0-8.0 | 13.0-16.5 | 20.0-24.0 | | (7.3) | (15.0) | (22.4) | | | | 32 |30 | 7.5-8.5 | 15.0-17.0 | 22.5-25.0 | | (7.8) | (16.1) | (23.8) | | | | 35 |35 | 8.0-9.0 | 15.0-19.5 | 23.0-27.5 | | (8.1) | (17.7) | (25.9) | | | | 37 |22 | 8.5-9.5 | 16.0-22.0 | 25.0-31.0 | | (9.0) | (18.8) | (27.8) | | | | 39 |14 | 9.5-10.5 | 19.0-24.9 | 28.5-33.5 | | (9.9) | (21.1) | (31.0) | | | | 40 |27 | 7.0-11.5 | 15.0-23.0 | 23.0-34.5 | | (9.1) | (22.0) | (31.2) | | | |