MEXICAN TAILLESS AMPHIBIANS 161 



mm. ; transverse diameter of tympanum, 5.5 mm. ; transverse diameter 

 of eye, 8.3 mm.; anterior edge of eye to nostril, 6.2 mm.; the hind 

 limb being carried forward along the body, the tibio-tarsal joint 

 reaches to center of eye; a sharp-edged tarsal fold from inner meta- 

 tarsal tubercle to tibio-tarsal joint; large inner and vestigial outer 

 metatarsal tubercle; vomerine teeth in two transverse series near 

 level of middle of choanae; upperparts \vith dark confluent spots and 

 interorbital black band; fore and hind limbs with dark cross bands; 

 skin on crown of head split longitudinally to expose fronto-parietal 

 region; body wall on left side damaged, exposing egg mass. 

 Ruthven ^^ says of this species: 



There was much variation in color in the specimens of H. baudini which we 

 examined in life. Occasional individuals were a dull orange *9 (about 153d) 

 above, but in by far the greater majority of the ground color of the back was dark 

 olive green (230), dark olive (180), dark brown (130 or 155) or dark orange (105). 

 The head was a shade lighter than the ground color in most specimens, and the 

 pale spot varied from a pale dull greenish tint (203d) to a very pale yellow (221) 

 or bright green (336). The belly was nearly always a light orange tint (116, 121, 

 136), and the light spots on the sides, light orange yellow (191). The dark mark- 

 ings vary greatly in distinctness. In the paler individuals they are usually 

 indistinct or even entirely wanting, except for faint traces. In those which have 

 a darker ground color they are usually distinct, particularly the black stripe from 

 the tympanic region to the shoulder. They also vary in arrangement, for they 

 may either be connected into a more or less irregular dorsal stripe or stripes, 

 beginning with the cross band between the eyes, or they may be in the form of 

 irregularly extended spots. 



We found H. baudini common at Cuatotolapam. Most of the specimens were 

 taken during night rains on the banana trees at San Juan. At these times they 

 were very noisj'. During the day we found them secreted under boards, in the 

 bases of such large leaved plants as the "elephant ears," bananas, etc. They 

 were observed breeding in a pond near La Laja Creek on July 17. 



Dr. E. W. Nelson states in his field catalogue that in wet weather 

 on June 10, 1895, three of these tree frogs were found on the ground 

 at an altitude between 900 and 1,200 feet in the mountains of Santo 

 Domingo, Oaxaca. On July 19, 1897, he found two of them hiding 

 under brick tiles on the roof of a veranda, where they uttered hoarse 

 croakings during the evening and at nightfall. 



As an illustration of the elusiveness of tree frogs. Dr. Hans Gadow ^° 

 contrasted an occurrence of countless numbers of Hyla haudinii 

 spawning in a wet meadow near Presidio south of Cordoba in Vera 

 Cruz with his fruitless search for this species on his subsequent travels 

 in Mexico. This experience is described as follows: 



Whilst rambling along the edge of the forest we became conscious of a noise, 

 at first resembling the mutter of a distant sawmill; but on our reaching the other 



" Ruthven, A. G., The amphibians and reptiles collected by the University of Michigran-Walker Expe- 

 dition in southern Vera Cruz, Mexico. Zool. Jahrb. (Syst. Abt.), vol. 32, pt. 4, pp. 310, 311, 1912. 



M The numbers refer to the "Code des Couleurs," by Klincksiek and Vallete. 



60 Oadow, H., Through southern Mexico: Being an account of the travels of a naturalist, London, pp.75, 

 76, 1908. 



