80 



BULLETIN 58^ UNITED STATES NATIONAL MUSEUM. 



Width of head. 

 Fore 



leg. 



mm. 

 12 

 23 



Hind leg from vent to i\\) of longest toe 57 



Tibia 16. 5 



Foot from base of inner metatarsal tubercle to tip of longest toe 18 



Inner metatarsal tubercle 2 



The adult male has a hirge external, dark-pigmented, vocal sac 

 under the throat, folding up with longitudinal folds when not inflated. 

 The males of U.S.N.M. No. 7428, which were collected by Dr. Wm. 

 Stimpson, at Simoda, in May, 1855, consequently during the breed- 

 ing season, have a large and distinct pad of nuptial asperities on the 

 upper side of the base of the first finger, but they are not distinguished 

 from the adj acent skin by any different coloration. The color of these 

 specimens, which have the back unspotted, is described from life by 

 Stimpson as being ''bright light green above; a golden band along 

 each side of the head, including the eye; sides minutely sprinkled 

 with copper color; belly white." 



Variation. — In the series before me the structural and proportional 



characters, such as the size and shape 

 of the vomerine series of teeth, the 

 size of tympanum, digital disks, and 

 metatarsal tubercle, vary within cer- 

 tain limits. The length of the foot 

 is found to vary considerably in a 

 few specimens, apparently without 

 being correlated with any other 

 difference. It is in the coloration, 

 however, that we meet with the 

 greatest amount of variation. Not 

 only are many of the specunens 

 entirely uniform above, but the lat- 

 eral stripe is scarcely indicated in a 

 large number, and the mark on the 

 tip of the snout is absent in most. 

 The dusky spot beneath the eye is present in a majority, and the 

 crossbars on the tarsus are visible in all the specimens which are not 

 so faded from age as to have lost nearly all trace of markings. In 

 the specimens with dorsal spots the angular shoulder mark is usually 

 present^ but in No. 23542, at least, there is a longitudinal stripe on 

 each side of the back, caused by a fusion of the two dorsal spots 

 a,nd the obliteration of the transverse branch of the anterior mark. 



Habitat. — The tree-toad, a name probably preferal^le to tliat of 

 tree-frog, which may properly be restricted to the genus Polypedates 

 (or RTiacophoims of many authors), occurs all over Japan proper in 

 suitable stations. It is hardly necessary to enumerate specific locali- 



FiGS. 68-70.— Hyla arborea japonica. 1^ X 



NAT. SIZE. 68, TOP OF HEAD; 69, SIDE OF 

 head; 70, UNDERSIDE OF FOOT. No. 212U, 



U.S.N.M. 



