386 The American Naturalist. [May, 
matter, which is dissolved by the moisture in the rainy sea- 
son when they become detached and drop into the water 
where they are hatched. A similar phenomenon has been 
observed in the case of one of the Hylidse which has its hab- 
itat in Southern Brazil ; but in neither case has it been ob- 
served that the eggs hatch while attached to the trees. In 
the case of the Japanese Batrachian it is plain that the hatch- 
ing takes place upon the trees and the larva possibly under- 
goes some of its transformations in the nidus suspended among 
the branches. Whether the glairy mass is due to the swell- 
ing, under the action of the semi-tropical rains, of material 
deposited by the female at the time of oviposition I cannot 
tell. As against this view is the fact that the dried scum after 
prolonged soaking in water fails to regain its old vesicu- 
lar, bubbly form. It may be that the froth is secreted by the 
bodies of the tadpoles themselves, or that both the tadpoles 
and the parent batrachian are concerned in its production 
The large quantity of the mass favors the latter view. The 
nests were fully a foot in diameter. The presence of dead in- 
sects in large numbers in the midst of the masses as well as 
adhering to its outside suggests that the tadpoles feed upon 
these. 
I looked diligently for the adult batrachian in the vicinity, 
but failed to discover any frogs in the trees near by or in the 
pool. Later in the season the trees and bushes are fully alive 
in places with Hylidae. 
I trust some observer with better opportunities than I had 
in my brief and hurried visit to Nikko will solve the mysteries 
of the life history of these arboreal tadpoles. 
EXPLANATION OF PLATE XVII. 
Fig. I. Section of nest one-third natural size, representing 
internal structure and position of tadpoles in the mass. 
Fig. 2. Sketch presenting a view of the position of the 
tadpoles amidst the vesicles. (Enlarged.) 
