140 BULLETIN 160, UNITED STATES NATIONAL MUSEUM 



1864. Agalychnis Cope, Proc. Acad. Nat. Sci. Philadelphia, vol. 16, p. 181, Aug. 

 [Genotype, Hyla callidryas Cope, 1862, Proc. Acad. Nat. Sci. Philadelphia, 

 vol. 14, p. 359, footnote, Sept. (Panama).] — Cope, 1865, Proc. Acad. Nat. 

 Sci. Philadelphia, vol. 17, p. 194, Oct. 



There are three species of Phyllomedusa in Mexico, and the ranges 

 of two of these extend southward into Central America. Related 

 species occur in Central and South America. Some of the species 

 have rather bizarre and striking color schemes. The largest one, 

 P. bicolor, which is found in Guiana and BrazU, has a body length of 

 110 mm., and the smallest, P. perlata, a native of northeastern Peru, 

 measures onlj'^ 23 mm. Large individuals of a Mexican species, P. dacni- 

 color, may attain a body length of 90 mm. These frogs are supposedly 

 nocturnal in habit, for all of them have eyes with vertical pupils, and 

 presumably spend most of their Uves in arboreal surroundings. Most 

 of them have an eye with a red iris, and the body color is some shade 

 of green. In one of the Mexican species, P. dacnicolor, the iris is 

 black, vermiculated with gold. The viscous under surfaces of the 

 large adhesive disks enable these frogs to attach themselves to the 

 surfaces of leaves, limbs, and trunks of trees and shrubs. It is gen- 

 erally thought that those that have the hind toes united by a web or 

 membrane are best fitted for swimming in water, and if this be true 

 P. moreletiiwith. its extensively webbed fingers and toes is exceptionally 

 well adapted for this purpose. One of the Mexican species, P. dacni- 

 color, seems to be as much at home on the ground in the grass as it is 

 when hidden in the foliage of trees and shrubs. Some species of 

 Phyllomedusa merely deposit their eggs on the upper surface of leaves 

 overhanging the water, while others seemingly succeed in curling leaves 

 around the egg mass. After several days in the egg mass the tadpoles 

 lose their external gills and drop into the water, where the metamor- 

 phosis is completed. 



The supposedly least specialized species of these neotropical tree 

 frogs were allocated to the genus Agalychnis by Cope. In character- 

 izing the genus Agalychnis he cited the elongation of the inner toes, 

 which are more or less opposable, the deeply emarginate xiphisternum, 

 and the fact that the inferior palpebra is latticed or reticulated with 

 strong white veins. In formulating the diagnoses for the genera 

 Phyllomedusa and Agalychnis, Boulenger in 1882 made no reference 

 to some of the characters cited by Cope, and introduced other struc- 

 tural characters overlooked by him. Although a number of structural 

 features are hsted in each, the diagnosis of Agalychnis differs from that 

 of Phyllomedusa solely in having the " first [fingers and toes] opposite to 

 the others." It has been confirmed by direct observation of hving 

 Phyllomedusa that the first finger and the first toe usually oppose the 

 other digits when some small branch is grasped. This faculty of 

 opposing the inner finger and the inner toe is by no means confined 

 to the limited group formerly segregated under the name of Agalych- 



